Question

expand each of the following using suitable identities.

1)(3a-7b-c)square with step pls because I am studying.
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Answer 1

$\huge\underline\bold\red{\mathfrak{Answer}}$

Apply identity =>

➛(3a-7b-c)²

➛(3a)²+(-7b)²+(-c)²+2(3a)(-7b)+2(-7b)(-c)+2(3a)(-c)

➛9a²+49b²+c²-42ab+14bc-6ac

★Identity used here★

(a+b+c)² = a²+b²+c²+2ab+2bc+2ac

Hope it helps :)