How do you find the 2nd term in the expansion of (y-2x)^4?

1 Answer
Sep 1, 2016

"The reqd. term"=-8y^3x.

Explanation:

In the Binomial Expansion of (a+b)^n, the general (r+1)^(th) term,

i.e., T_(r+1), is given by,

T_(r+1)=""_nC_r*a^(n-r)*b^r.

In our example, n=4, a=y, b=-2x, r+1=2, i.e., r=1

:. T_(1+1)=T_2=""_4C_1*y^(4-1)*(-2x)^1

=4*y^3*(-2x)

=-8y^3x.