Question

Evaluate (3b - 2c)2 using suitable identity

Answer 1

Given:- (3b-2c)²

Using:- (a-b)²=a²+b²-2ab.

(3b)²+(2c)²-2×3b×2c

9b²+4c²-12bc.

Answer 2

Answer:

Step-by-step explanation:

→ By using the 5th Algebraic identity we will solve this equation. The 5th says that (a+b+c)² = a²+b²+c²+2ab+2bc+2ca. then we will do the square of 2, 3 and 2 which are a, b and c.

→ And the we will multiply the numbers which are given in the brackets and then we will multiply it with 2 which is outside the bracket as shown above.

→ After equating the whole expression the final answer is 4a² + 9b² + 4c² + 12ab + 12 bc + 8ca.

_____________________________________