Question

(using identities) if a^2 + b^2 = 13 and ab= 6 find 3(a+b)^2 - 2(a-b)^2​

Answer 1

Step-by-step explanation:

a²+b²=13

ab=6

(a+b)²=a²+b²+2ab

(a+b)²=13+2(6)

(a+b)²=13+12

(a+b)²=25

(a-b)²=a²+b²-2ab= 13-2(6)= 13-12= 1

3(a+b)²-2(a-b)² = 3(25)- 2(1) = 75-2 = 73