Question

Expand (a+b+c)square ​

Answer 1

(a + b + c)²

[(a+b) + c]²

(a+b)² + c² + 2c(a+b)

a² + b² + 2ab + c² + 2ac + 2bc

a² + b² + c² + 2ab + 2ac + 2bc

Identity used → (x+y)² = x² + y² + 2xy

Answer 2

${(a + b + c)}^{2} \\ =( ( a + b) + {c)}^{2} \\ = ( {a + b)}^{2} + 2(a + b)c + {c}^{2} \\ = ( {a}^{2} + {b}^{2} + 2ab ) + (2ac + 2bc ) + {c}^{2} \\ = {a}^{2} + { b}^{2} + 2ab + 2ac + 2bc + {c}^{2} \\ ={a}^{2} + {b}^{2} + {c}^{2} + 2ab + 2bc + 2ac$