Write the following cubes in expanded form: (2x+1)3
(2x+1)3
Using identity (x+y)3 = x3 + y3 + 3xy(x + y)
= (2x)3 + (1)3 + 3(2x)(1)(2x + 1)
= 8 x3+ 1 + 6x(2x + 1)
= 8x3 + 1 + 12x2 + 6x
Write the following cubes in expanded form:
(3x2+1)3
Write the following cubes in expanded form: (i) (2x+1)3 (ii) (2a−3b)3