Question

Evaluate using identities :
a) (3y²-z)³
b) 4x²-9y²

Answer 1

Step-by-step explanation:

a) (3y^2-z)^3

solution:-

we know that,

[(a-b)=a^3-3a^2b+3ab^2-b^3]

=[(3y^2)^3-3(3y^2)(z)+3(3y^2)(z)^2-(z)^3]

=[27y⁶-9y²z+9y²z²-z³]

b) 4x²-9y²

solution:-

we know that,

[(a²-b²)=(a-b)(a+b)]

=(2x)²-(3y)²

=(2x+3y)(2x-3y)