Q 1 :

The zeroes of the polynomial x23xm(m+3) are

  • m,m+3

     

  • -m,m+3

     

  • m,-(m+3)

     

  • -m,-(m+3)

     

(2)

Let p(x)=x2-3x-m(m+3)

p(x)=x2-(m+3)x+mx-m(m+3)

=x{x-(m+3)}+m{x-(m+3)}

For zeros of p(x)

p(x)=(x+m){x-(m+3)}=0x=-m,m+3

 Its zeros are -m,m+3



Q 2 :

If α and β are the zeros of a polynomial f(x)=px22x+3p and α + β = αβ, then p is

  • -2/3

     

  • 2/3

     

  • 1/3

     

  • -1/3

     

(2)

Given, f(x)=px2-2x+3p

Since α and β are the zeroes of the given polynomial.

 α+β=-(-2)p=2p, and αβ=3pp=3

 α+β=αβ      (given)

 2p=3p=23



Q 3 :

The zeroes of a polynomial x2+px+q are twice the zeroes of the polynomial 4x25x6. The value of p is :

  • -5/2

     

  • 5/2

     

  • -5

     

  • 10

     

(1)

Given polynomials : x2+px+q   ...(i)

and 4x2-5x-6       ...(ii)

Zero of polynomial 4x2-5x-6 are: x=2 and x=-3/4

Now, zero of polynomial x2+px+q are 4 and -3/2

 Sum of zeroes =-p1

4-32=-p1-p=52p=-52



Q 4 :

If the sum of zeroes of the polynomial p(x)=2x2-k2x+1 is 2, then value of k is :

  • 2

     

  • 2

     

  • 22

     

  • 1/2

     

(2)

Sum of zeroes =2=-(-k2)2k=2

 



Q 5 :

If α and β are zeroes of the polynomial 5x2+3x7, the value of 1α+1β is

  • −3/7

     

  • 3/5

     

  • 3/7

     

  • −5/7

     

(3)

α+β=-ba=-35,  αβ=ca=-75

Now, 1α+1β=α+βαβ=-35-75=37

 



Q 6 :

Consider the polynomial p(x) = x³  3x² + 2x. Which of the following statements are true about its graph and zeros?

(i) The polynomial has a zero at x = 0.
(ii) The polynomial has a zero at x = 1.
(iii) The graph touches the x-axis at x = 1.
(iv) The graph intersects the x-axis at x = 2.

 

Choose the correct option from the following:

  • both (i) and (ii)

     

  • both (ii) and (iii)

     

  • (i), (ii) and (iv)   

     

  • both (i) and (iv)

     

(3)

p(x) = x³  3x² + 2x p(x) = x(x²  3x + 2) p(x) = x(x  2)(x  1)

Factoring p(x) gives x(x – 1)(x – 2), indicating zeros at x = 0, 1, and 2. The graph intersects the x-axis at these points.



Q 7 :

For the polynomial r(x) = x² – 4x + 4, which of the following statements are correct about its graph and zeros?

 

 

(i) The graph touches the x-axis at x = 2.
(ii) The graph intersects the x-axis at x = 2.
(iii) The polynomial is equivalent to (x – 2)².
(iv) The vertex of the graph is at the point (2, 0).

 

Choose the correct option from the following:

  • (i), (iii) and (iv)

     

  • (ii) and (iii)

     

  • (i), (ii) and (iv)

     

  • (i) and (iv)

     

(1)

Given polynomial r(x) can be rewritten as (x – 2)², indicating a repeated zero at x = 2. The graph touches the x-axis at this point and does not cross it. The vertex of the graph is at point (2, 0).



Q 8 :

For the polynomial t(x) = x³ – 6x² + 11x – 6, which statements are true about its graph and zeros?

(i) The polynomial has a zero at x = 1.
(ii) The polynomial has a zero at x = 2.
(iii) The graph of the polynomial intersects the x-axis at x = 3.
(iv) The polynomial can be factorised as (x – 1)(x – 2)(x – 3).

Choose the correct option from the following:

  • (i), (iii) and (iv)

     

  • (i), (ii), (iii) and (iv)      

     

  • (i), (ii) and (iv)

     

  • (i) and (iv)

     

(2)

At x = 1, t(1) = 1 – 6 + 11 – 6 = 0

So (x – 1) is a factor of t(x).

∴ t(x) = (x – 1)(x² – 5x + 6)

⇒ t(x) = (x – 1)(x – 2)(x – 3)

Factoring t(x) as (x – 1)(x – 2)(x – 3) reveals zeros at x = 1, 2, 3. The graph intersects the x-axis at these points.



Q 9 :

Shown below is a part of the graph of a polynomial h(x).

On dividing h(x) by which of the following will the remainder be zero?

(i) (x – 2)
(ii) (x + 2)
(iii) (x – 4)
(iv) (x + 4)

Choose the correct option from the following:

  • only (ii)

     

  • only (i) and (iii)

     

  • only (ii) and (iv)

     

  • cannot be determined without knowing the polynomial h(x).

     

(1)

Since the given graph intersects the x-axis at x = –2, therefore (x + 2) is a factor of h(x).

So, on dividing h(x) by (x + 2), we get remainder zero

 



Q 10 :

If the sum of zeros of the polynomial p(x) = 2x²  k2x + 1 is 2, then value of k is:

  • √2         

     

  • 2

     

  • 2√2      

     

  • 1/2

     

(2)

Given polynomial is p(x) = 2x² – k√2x + 1.

Let α, β be its zeros then

α + β = –b/a = –(–k√2)/2 = k√2/2 = √2

[Here a = 2, b = –k√2, c = 1]

⇒ k√2 = 2√2 ⇒ k = 2



Q 11 :

If α and β are the zeros of the polynomial p(x) = kx² – 30x + 45k and α + β = αβ, then the value of k is:

  • –2/3

     

  • –3/2     

     

  • 3/2       

     

  • 2/3

     

(4)

Given polynomial is p(x) = kx² – 30x + 45k.

We know α + β = –b/a and αβ = c/a

⇒ α + β = 30/k and αβ = 45k/k = 45

Given α + β = αβ ⇒ 30/k = 45 ⇒ k = 30/45 = 2/3

 



Q 12 :

The zeros of the quadratic polynomial 2x² – 3x – 9 are:

  • 3, –3/2

     

  • –3, –3/2

     

  • –3, 3/2

     

  • 3, 3/2

     

(1)

Given quadratic polynomial is 2x² – 3x – 9.

For zeros, we have 2x² – 3x – 9 = 0 ⇒ 2x² – 6x + 3x – 9 = 0 ⇒ (x – 3)(2x + 3) = 0

⇒ x = 3 or x = –3/2

 



Q 13 :

The number of quadratic polynomials having zeros –5 and –3 is:

  • 1

     

  • 2

     

  • 3

     

  • more than 3

     

(4)

Given: zeros of the polynomial are –5 and –3.

Polynomials having zeros –5 and –3 are given by p(x) = k(x + 5)(x + 3).

⇒ p(x) = k(x² + 8x + 15), where k is any real constant.

∴ k can have infinitely many values. So, number of possible polynomials is infinitely many.



Q 14 :

If one zero of the polynomial x² + 3x + k is 2, then the value of k is:

  • –10       

     

  • 10

     

  • 5

     

  • –5          

     

(1)

Given: one zero = 2.

∴ Substituting x = 2, we get 2² + 3(2) + k = 0 ⇒ 4 + 6 + k = 0 ⇒ k = –10



Q 15 :

The degree of polynomial having zeros –3 and 4 only is:

  • 2

     

  • 1

     

  • more than 3

     

  • 3

     

(1)

The degree of polynomial having zeros –3 and 4, i.e., only two zeros, is 2 because it will be a quadratic polynomial.

i.e., p(x) = (x – (–3))(x – 4) ⇒ p(x) = (x + 3)(x – 4) ⇒ p(x) = x² – x – 12, which is a polynomial of degree 2.



Q 16 :

Which of these are the quotient and the remainder when (2x³ – 9x + 3x² + 12) is divided by (x – 1)?

  • quotient = (2x² – 7x – 4) and remainder = 8

     

  • quotient = (2x² + 7x + 4) and remainder = 16
     

  • quotient = (2x² + 5x – 4) and remainder = 8
     

  • quotient = (2x² + 5x + 4) and remainder = 16
     

(3)

Divide dividend by divisor, we get:

x – 1 | 2x³ + 3x² – 9x + 12
        2x² + 5x – 4

So, the quotient is 2x² + 5x – 4 and remainder is 8.



Q 17 :

Let p be a prime number. The quadratic equation having its roots as factors of p is:

  • x² – px + p = 0

     

  • x² – (p + 1)x + p = 0

     

  • x² + (p + 1)x + p = 0      

     

  • x² – px + p + 1 = 0

     

(2)

Since p is a prime number, its factors are 1 and p itself. So, α = 1 and β = p.

General form of quadratic equation: x² – (sum of zeros)x + product of zeros = 0.

⇒ x² – (1 + p)x + p = 0 is the required quadratic equation.

 



Q 18 :

If α and β are two zeros of a polynomial f(x) = px² – 2x + 3p and α + β = αβ, then p is:

  • –2/3

     

  • 2/3

     

  • 1/3

     

  • –1/3

     

(2)

Given polynomial is f(x) = px² – 2x + 3p.

So, α + β = –b/a = –(–2)/p = 2/p and αβ = c/a = 3p/p = 3 [a = p, b = –2, c = 3p].

Since α + β = αβ ⇒ 2/p = 3 ⇒ p = 2/3