Q.

The number of distinct real roots of the equation |x+1||x+3|-4|x+2|+5=0 is ________.         [2024]


Ans.

(2)

|x+1||x+3|-4|x+2|+5=0

(I) If x<-3,  x2+4x+3+4x+8+5=0

x2+8x+16=0x=-4 (one solution)

(II) If -3x<-2,  -x2-4x-3+4x+8+5=0

x2-10=0x=±10

which do not satisfy -3x<-2

(III) If -2x<-1,  -x2-4x-3-4x-8+5=0

x2+8x+6=0(x+4)2=10

x=-4±10 which do not satisfy -2x<-1

(IV) If x-1,  x2+4x+3-4x-8+5=0

x2=0x=0 (one solution)

Hence, the number of distinct real roots are two.