Question

please answer this three plz​

Answer 1

identity going to be used :

(a + b + c)² = a² + b² + c² + 2 (ab + bc + ac)

$\sf \: i) {(a + 2b + c)}^{2} \\ \\ ⇨ \purple{\sf{a}^{2} + {4b}^{2} + {c}^{2} + 2(a + 2b + c) }\\ \\ \\ \sf \: ii) {(2a - 3b - c)}^{2} \\ \\ ⇨ \purple{ \sf {4a}^{2} + {9b}^{2} + {c}^{2} + 2( 2a - 3b - c)} \\ \\ \\ \sf \: iii) {( - 3x + y + z)}^{2} \\ \\ ⇨\purple{\sf{9x}^{2} + {y}^{2} + {z}^{2} + 2( - 3x + y + z)}$

Here's your answer.!

©RudranshuMishra7