If `(x+2) and (x-1) ` are factors of `(x^3+10x^2+mx+n)` thenA. `m=5,n=-3`B. `m=7,n=-18`C. `m=17,n=-8`D. `m=23,n=-19`

If `(x+2) and (x-1) ` are factors of `(x^3+10x^2+mx+n)` thenA. `m=5,n=

1.	If `(x+2) and (x-1) ` are factors of `(x^3+10x^2+mx+n)` thenA. `m=5,n=-3`B. `m=7,n=-18`C. `m=17,n=-8`D. `m=23,n=-19`
Answer» Correct Answer - B Let ` (x)=x^3+10x^2+mx+n`. Then, `p(-2)=0 and p(1)=0`. `(-2)^3+10xx (-2)^2+mxx (-2)+n=0rArr n-2m=32` `(1)^3+10xx (1)62+m xx 1 +n=0rArr n+m=-11......(i)` `therefore m=7and n=-18 ..........(ii)`