If the coefficient of x in the expansion of (x2+kx)5 is 270, then k =
1
2
3
4
Tr+1 = 5Cr(x2)5−r(kx)r
For coefficient of x, 10 - 2r - r = 1 ⇒ r = 3
Hence, T3+1 = 5C3(x2)5−3(kx)3
According to question, 10k3 = 270 ⇒ k = 3.
If the coefficient of x in (x2+kx)5 is 270, then k =
If the coefficient of x in (x2+λx)5 is 270, then λ=