Question

Using identity (3x^2-4y^2) (3x^2-4y^2)

Answer 1

ANSWER:

• Value of the above expression is 9x⁴+16y⁴-24x²y²

GIVEN:

• (3x²-4y²)(3x²-4y²)

TO FIND:

• Value of above expression.

SOLUTION:

= (3x²-4y²)(3x²-4y²)

= (3x²-4y²)²

= (3x²)²+(4y²)²-2×3x²×4y²

= 9x⁴+16y⁴-24x²y²

IDENTITY USED:

• (a+b)² = a²+b²+2ab

NOTE:

Some important formulas:

(a+b)² = a²+b²+2ab

(a-b)² = a²+b²-2ab

(a+b)(a-b) = a²-b²

(a+b)³ = a³+b³+3ab(a+b)

(a-b)³ = a³-b³-3ab(a-b)

a³+b³ = (a+b)(a²+b²-ab)

a³-b³ = (a-b)(a²+b²+ab)

(a+b)² = (a-b)²+4ab

(a-b)² = (a+b)²-4ab