Question

Expand: (3a-4b+5c)2
9a2+16b2+25c2-24ab+40bc-30ac
9a2+16b2+25c2-24ab-40bc-30ac
9a2+16b2+25c2-24ab-40bc+30ac​

Answer 1

Answer:

=> 9a^2 + 16b^2 + 25c^2 - 24ab - 40bc

+ 30ac

Explanation:

Since (a - b + c)^2 = a^2 + b^2 + c^2

-2 × a × b -2 × b × c +

2 × c × a

Therefore (3a - 4b + 5c)^2

=> (3a)^2 - (4b)^2 + (5c)^2 - 2 × 3a × 4b - 2

× 4b × 5c + 2 × 5c × 3a

=> 9a^2 + 16b^2 + 25c^2 - 24ab - 40bc +

9a^2 + 16b^2 + 25c^2 - 24ab - 40bc +

30 ca