Question

(3a-b)² please help me with the sum

Answer 1

${9a}^{2} + {b}^{2} - 6ab$
this is your answer.....

Answer 2

$given$
(3a - b)^2

In this (a -b )^2 identity will apply

i.e a^2 +b^2 - 2ab


so ans would be


(3a)^2 +(b)^2 -2(3a)(b)


$9 {a}^{2} + {b}^{2} - 6ab$