M4maths Previous Puzzles

19 Jul 2012 x

if x^3+3x^2+2x+5=0
then (x+1)^3 will be

OPtion

1) x+3
2) x+5
3) x+8
4) x+1
5) x-1
6) x-3
7) x-5
8) x-6
9) x-4
10) none of these

Solution

(x+1)^3 = x^3+3x^2+3x+1 = (x^3+3x^2+2x+5)+(x-4) = 0 + (x-4)

Correct Option: 9 Best Solution (0)