Question

Find the coefficient of x⁷ in the expansion of (1 – x²+ x³) (1 + x)¹⁰.​

Answer 1

[ ( 2x ) + ( -3y ) + ( 4z ) ]² . Here, a = 2x , b = -3y and c = 4z . ( 2x )² + ( -3y )² + ( 4z )² + 2(2x)(-3y) + 2(-3y)(4z) + 2(4z)(2x) . = 4x² + 9y² + 16z² - 12xy - 24yz + 16zx