Q 11 :

The area of the region {(x,y):x2+4x+2y|x+2|} is equal to         [2025]

  • 5

     

  • 7

     

  • 24/5

     

  • 20/3

     

(4)

We have, x2+4x+2y|x+2|

 (x+2)22y|x+2|

   Required area =42|(x2)(x+2)2+2|dx+20|(x+2)(x+2)2+2|dx

=42|x(x+2)2|dx+20|x(x+2)2+4|dx

=[|x22(x+2)33|]42+[|x22(x+2)33+4x|]20

=103+103=203.



Q 12 :

The area of the region enclosed by the curves y=exy=|ex1| and y-axis is:          [2025]

  • loge2

     

  • 1loge2

     

  • 2loge21

     

  • 1+loge2

     

(2)

Given: Region is bounded by curves y=ex and y=|ex1|.

The graph is given by

When ex=|ex1|

 ex=ex+1                              [ex-1<0]

 2ex=1  ex=1/2  x=ln(2)

Now, area is given by.

A=ln(2)0[ex(1ex)]dx=ln(2)0(2ex1)dx

=(2exx)ln(2)0=21ln(2)=1ln(2).



Q 13 :

The area of the region {(x,y):0y2|x|+1, 0yx2+1, |x|3} is         [2025]

  • 173

     

  • 323

     

  • 643

     

  • 803

     

(3)

Given, the area of region

{(x,y):0y2|x|+1, 0yx2+1, |x|3}

   Required area =202(x2+1)dx+23(2x+1)dx

                                    =2[(x33+x)02+(2x22+x)23]

                                    =2[83+2]+2(6)

                                    =2[143]+12

=643 sq. units.



Q 14 :

The area of the region bounded by the curves x(1+y2)=1 and y2=2x is :         [2025]

  • 2(π213)

     

  • π413

     

  • π213

     

  • 12(π213)

     

(3)

We have, x(1+y2)=1         ... (i)

and y2=2x          ... (ii)

From equation (i) and (ii), we get

x(1+2x)=1 2x2+x1=0

 x=12, x=1          (Reject)

From (ii), y2=2(12)  y=±1

   Required area =11(11+y2y22)dy

                                   =(tan1y-y36)|11=π2-13.



Q 15 :

Let the area of the region {(x,y):2yx2+3, y+|x|3, y|x1|} be A. Then 6A is equal to :           [2025]

  • 14

     

  • 16

     

  • 18

     

  • 12

     

(1)

Required area, A = Rectangle ABDE – Area of region EDC

 A=4201((3x)(x2+32))dx

 A=42{3xx22x3632x}01

 A=42{3121632}=73

So, 6A = 14.



Q 16 :

Let the area enclosed between the curves |y|=1x2 and x2+y2=1 be α. If 9α=βπ+γ; β, γ are integers, then the value of |βγ| equals           [2025]

  • 27

     

  • 15

     

  • 33

     

  • 18

     

(3)

We have, c1 : |y|=1x2 and c2 : x2+y2=1

   Required area =α=4[(Area of circle in1st quadrant)01(1x2)dx]

=4[(π(1)4)[xx33]01]

=4[π4(113)]=4[π423]

=π83

Hence, 9α=9π24

On comparing with 9α=βπ+γ, we get β=9 and γ=24

  |βγ|=|9(24)|=33.



Q 17 :

If the area of the region {(x,y):|4x2|yx2, y4, x0} is (802αβ), α, βN, then α+β is equal to _________.          [2025]



(22)

Required area =22(x2(4x2))dx+(222)×4222(x24)dx

=[2x334x]22+828[x334x]222

=402316=80266

 α=6, β=16

 α+β=22.



Q 18 :

The area of the region bounded by the curve y = max {|x|,x|x2|}, the x-axis and the lines x = –2 and x = 4 is equal to _________.          [2025]



(12)

Required Area = Area of OAB + Area of region OCDEO

=12×2×2+01(2xx2)dx+13xdx+34(x22x)dx

=2+23+4+163

= 12 sq. units.



Q 19 :

If the area of the region {(x,y):|x5|y4x} is A, then 3A is equal to __________.          [2025]



(368)

Area A=1254xdx12×4×412×20×20

                =[4x3/2×23]125208

                =83(1251)208

                =3683 sq. units

 3A=368.



Q 20 :

Let the area of the bounded region {(x,y):09xy2, y3x6} be A. Then 6A is equal to __________.          [2025]



(15)

We have,  09xy2, y3x6

Required area = A=|03y29dy+36(y+63)dy|

                                  =|19[y33]03+13(y22+6y)36|

                                  =|19[90]+13[183692+18]|

                                  =|1+13[92]|

                                  =|132|=|52|=52 sq. units

  6A=6×52=15



Q 21 :

Let the function, f(x)={3ax22,x<1a2+bx,x1 be differentiable for all xR, where a > 1, bR. If the area of the region enclosed by y = f(x) and the line y = –20 is α+β3, α, βZ then the value of α+β is __________.           [2025]



(34)

Given, f(x) is continuous and differentiable at x = 1.

f(x)={3ax22,x<1a2+bx,x1

 f'(x)={6ax,x<1b,x1

L.H.L. at x=1  3a2

R.H.L. at x=1  a2+b

   L.H.L. = R.H.L.          { f(x) is continuous}

 3a2=a2+b          ... (i)

L.H.D. at x=1  6a

R.H.D. at x=1  b

   L.H.D. = R.H.D.          [ f(x) is differentiable]

 6a=b          ... (ii)

From (i) and (ii), we get

3a2=a2-6a

 a23a+2=0  (a1)(a2)=0

 a=1 or a=2  a=2           ( a > 1)

From (ii), b = –12

Now, f(x)={6x22,x<1412x,x1

  Area of region =31(6x22+20)dx+12(412x+20)dx

=(6x332x+20x)31+(4x12x22+20x)12

 16+123+6=22+123

 22+123=α+β3

So, α=22 and β=12

  α+β=22+12=34



Q 22 :

If the area of the larger portion bounded between the curves x2+y2=25 and y=|x1| is 14(bπ+c), b, cN, then b + c is equal to __________.          [2025]



(77)

Given, x2+y2=25

 x2+(x1)2=25          [ y = |x –1|]

 x=4,3

   Required area =25π(34(25x2|x1|)dx)

=25π[12x25x2+252sin1x5]34+31(1x)dx+14(x1)dx

=25π+252(2×3+252sin1(45)+32×4+252sin1(35))

=25π+2521225π4

=75π4+12=14(75π+2)

  14(bπ+c)=14(75π+2)

 b=75, c=2

 b+c=77.



Q 23 :

The area bounded by the curves y=|x-1|+|x-2| and y=3 is equal to               [2023]
 

  • 6

     

  • 3

     

  • 5

     

  • 4

     

(4)

Required area is shaded in the given figure, which is a trapezium.

  Area=12×Sum of parallel sides×Height

=12×(AB+CD)×AM=12(1+3)×2=4 sq. units



Q 24 :

The area of the region {(x,y):x2y8-x2, y7} is         [2023]
 

  • 24

     

  • 20

     

  • 18

     

  • 21

     

(2)

We have,

x2y

8-x2y

y7

Converting the given inequations into equations, we get  x2=y and y=8-x2

Solving these equations to find their point of intersection

i.e.,  x2=8-x2

2x2=8x2=4x=±2

  y=4

Required area=-22(8-x2-x2)dx- -11(8-x2-7)dx

=-22(8-2x2)dx--11(1-x2)dx=[8x-23x3]-22-[x-x33]-11

=[(16-163)-(-16+163)]-[23+23]

=16-163+16-163-43=20 sq. units



Q 25 :

Area of the region {(x,y):x2+(y-2)24, x22y} is        [2023]
 

  • 2π-163    

     

  • π-83    

     

  • π+83    

     

  • 2π+163

     

(1)

Given that x2+(y-2)222 and x22y

Convert the given inequalities into equations:

x2+(y-2)2=4 and x2=2y

Solving circle and parabola simultaneously:

2y+y2-4y+4=4, y2-2y=0, y=0,2

Put y=2 in x2=2yx=±2 (2,2) and (-2,2)

A1=2×2-14·π·22=4-π

Required area=2[02x22dx-(4-π)]

=2[x36|02-4+π]=2[43+π-4]=2[π-83]=2π-163sq. units



Q 26 :

The area of the region enclosed by the curve y=x3 and its tangent at the point (-1,-1) is      [2023]

  • 274    

     

  • 314    

     

  • 234    

     

  • 194

     

(1)

Given, y=x3

Equation of tangent to the curve y=x3 at point (-1,-1) is

y+1=3(x+1)  y=3x+2

Point of intersection with the curve is (2,8)

So, area =-12[(3x+2)-x3]dx

=[3×x22+2x-x44]-12

=274 sq. units



Q 27 :

The area of the region enclosed by the curve f(x)=max{sinx,cosx}, -πxπ and the x-axis is         [2023]

  • 4(2)

     

  • 2(2+1)

     

  • 22(2+1)

     

  • 4

     

(4)

We have f(x)=max{sinx,cosx}, -πxπ

Now, the area of the region enclosed by the given curve and the x–axis is

=|-π-3π/4sinxdx|+|-3π/4-π/2cosxdx|+|-π/2π/4cosxdx|+|π/4πsinxdx|

=-12+1+1-12+12+1+1+12=4



Q 28 :

The area of the region {(x,y):x2y|x2-4|,y1} is            [2023]

  • 43(42+1)

     

  • 34(42-1)

     

  • 34(42+1)

     

  • 43(42-1)

     

(4)

Required area=2(12ydy+244-ydy)

=2([y3/23/2]12-[(4-y)3/23/2]24)

=43[(22-1)-(0-22)]=43(42-1)



Q 29 :

The area of the region given by {(x,y):xy8, 1yx2} is           [2023]

  • 16loge2-143

     

  • 8loge2-133

     

  • 8loge2+76

     

  • 16loge2+73

     

(1)

Area=12(x2-1)dx+28(8x-1)dx

=(x33-x)12+8(logex)28-(x)28

=43+8(2loge2)-6=16loge2-143



Q 30 :

The area enclosed by the curves y2+4x=4 and y-2x=2 is            [2023]

  • 233

     

  • 223

     

  • 9

     

  • 253

     

(3)

Given curves are y2+4x=4 and y-2x=2

The points of intersection of the given curves are (0, 2) and (- 3, - 4)

Required area=-42[(4-y24)-(y-22)]dy

=-42-y2-2y+84dy=14[-y33-y2+8y]-42

=14[(-83-4+16)-(643-16-32)]

=14[(283)-(-803)]=14(1083)=10812=9 sq. units.



Q 31 :

Let A={(x,y)2:y0, 2xy4-(x-1)2}

and B={(x,y)×:0ymin{2x,4-(x-1)2}}.

Then the ratio of the area of A to the area of B is                             [2023]

  • ππ+1    

     

  • π-1π+1    

     

  • π+1π-1    

     

  • ππ-1

     

(2)

Let A={(x,y)2:y0, 2xy4-(x-1)2}

and B={(x,y)×:0ymin{2x,4-(x-1)2}}

We have the following diagram y2+(x-1)2=4

Shaded portion A

Area A=area of quadrant of circle-area of (OAB)

              =π(4)4-12(2)(1)=(π-1)                      ...(i)

Now, for finding the area of portion B, we have

Area B=area of (AOB)+area of quadrant of circle

              =12·(1)(2)+π(2)24=(π+1)                     ...(ii)

Thus, according to the question, ratio of area A to area

B=π-1π+1



Q 32 :

Let Δ be the area of the region {(x,y)2:x2+y221, y24x, x1}. Then 12(Δ-21sin-127) is equal to          [2023]

  • 3-23

     

  • 23-23

     

  • 23-13

     

  • 3-43

     

(4)

If Δ be the area of region {(x,y)2:x2+y221, y24x, x1}. Then we have,

Area=2132xdx+2321(21-x2)dx

Δ=83·(33-1)+21sin-1(27)-63

[Δ-21sin-1(27)]=23-832

12[Δ-21sin-127]=3-43



Q 33 :

The area of the region A={(x,y):|cosx-sinx|ysinx, 0xπ2} is               [2023]

  • 5-22+1

     

  • 5+22-4.5

     

  • 1-32+45

     

  • 35-32+1

     

(1)

The area of the region, A={(x,y):|cosx-sinx|ysinx, 0xπ2}

|cosx-sinx|ysinx

For finding the intersecting point we must have  

cosx-sinx=sinx

tanx=12

Let ϕ=tan-112

So, tanϕ=12, sinϕ=15, cosϕ=25

Area=ϕπ/2(sinx-|cosx-sinx|)dx

=ϕπ/4(sinx-(cosx-sinx))dx+π/4π/2(sinx-(sinx-cosx))dx

=ϕπ/4(2sinx-cosx)dx+π/4π/2cosxdx

=[-2cosx-sinx]ϕπ/4+[sinx]π/4π/2

=5-22+1



Q 34 :

Let q be the maximum integral value of p in [0,10] for which the roots of the equation x2-px+54p=0 are rational. Then the area of the region 
{(x,y):0y(x-q)2, 0xq} is            [2023]

  • 164

     

  • 243

     

  • 1253

     

  • 25

     

(2)

Given equation is x2-px+54p=0

D=p2-5p, which is a perfect square when p=9.

  q=9

Required area=09(x-9)2dx

=09(x2-18x+81)dx=[x33-18×x22+81x]09

=243 sq. units.



Q 35 :

If the area of region S={(x,y): 2y-y2x22y, xy} is equal to n+2n+1-πn-1, then the natural number n is equal to _______ .    [2023]



(5)

Given, x2+y2-2y0; x2-2y0; xy

Area of segment OAB=90°360°×π(1)2-12×1×1

=(π4-12)

Hence, required area =02(x-x22)dx-(π4-12)

=(x22-x36)02 -(π-24)=2-43-π4+12=76-π4

Now, n+2n+1-πn-1=76-π4

For n=5n+2n+1-πn-1=76-π4         n=5



Q 36 :

Let the area enclosed by the lines x+y=2, y=0, x=0 and the curve f(x)=min{x2+34,1+[x]}, where [x] denotes the greatest integer x, be A. Then the value of 12A is____________ .             [2023]



(17)

 



Q 37 :

Let y=p(x) be the parabola passing through the points (-1,0),(0,1) and (1,0). If the area of the region

 {(x,y):(x+1)2+(y-1)21, yp(x)} is A, then 12(π-4A) is equal to ______ .         [2023]



(16)

There can be infinite parabola through given points.

In question, it must be given that axis of parabola is parallel to y-axis.

Equation of parabola passing through (-1, 0), (0, 1) and (1, 0) is x2=-(y-1)                     ...(i)

  Required area, A=-10[(1-x2)-(1-1-(x+1)2)]dx

=-10(-x2+1-(x+1)2)dx

=[-x33+x+121-(x+1)2+12sin-1(x+11)]-10

=12(π2)-13=π4-13

 12(π-4A)=12(π-4(π4-13))=12(43)=16



Q 38 :

If the area of the region {(x,y):|x2-2|yx} is A, then 6A+162 is equal to _______ .           [2023]


 



(27)

We have,   

Region={(x,y):|x2-2|yx}

The graph of the region is as shown in figure.

Required area, A=12[x-{-(x2-2)}]dx+22{x-(x2-2)}dx

=12(x2+x-2)dx+22(-x2+x+2)dx

=(x33+x22-2x)12+(-x33+x22+2x)22

=(223+1-22)-(13+12-2)+(-83+2+4)-(-223+1+22)

=27-1626       6A+162=27-162+162=27



Q 39 :

If A is the area in the first quadrant enclosed by the curve C: 2x2-y+1=0, the tangent to C at the point (1, 3) and the line x+y=1, then the value of 60A is ______ .    [2023]


 



(16)

Given, C:2x2-y+1=0

4x-dydx=0 dydx=4x [dydx](1,3)=4

Equation of tangent to the curve C is

     y-3=4(x-1)

y-4x+1=0    ...(i)

Also, given line is x+y=1    ...(ii)

Solving (i) and (ii), we get x=0.4, y=0.6

Given curve and equation (ii) intersect each other at (0,1) and (-0.5,1.5).

Required area,  

A=01(2x2+1)dx-area of EOA-area of BED+area of EDC

=[2x33+x]01-12×1×1-12(1-14)×3+12×(1-14)×0.6

=(23+1)-12-98+940=1660 sq. units

   60A=1660×60=16



Q 40 :

If the area bounded by the curve 2y2=3x, lines x+y=3, y=0 and outside the circle (x-3)2+y2=2 is A, then 4(π+4A) is equal to _____ .       [2023]


 



(42)

Given, y2=3x2, x+y=3, y=0, and (x-3)2+y2=2

2y2=3(3-y)

2y2+3y-9=0 2y2-3y+6y-9=0

(2y-3)(y+3)=0y=32,-2

Required area, A=032((3-y)-2y23)dy-π8(2)

=(3y-y22-2y39)03/2-π4=3×32-98-29(278)-π4

=92-98-34-π4

 4A+π=4[92-98-34]=212=10.50

  4(4A+π)=42