(a+5)² = (a+5)*(a+5) = a² + 5a +5a + 25 = a² + 10a + 25

(4-3b)² = (4-3b)*(4-3b) = 16 -12b - 12b +9b² = 16 -24b +9b²

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

= a² + b² + c² + 2ab + 2ac + 2bc

(a-b)³ = (a-b)*(a-b)*(a-b) = (a² - 2ab + b²)*(a - b) =

= a³ - a²b - 2a²b + 2ab² + ab² - b³ = a³ - 3a²b + 3ab² - b³

Verified answer

(a+5)2=(a+5)(a+5)=a2+5a+5a+25=a2+10a+25

(4−3b)2=(4−3b)(4−3b)=16−12b−12b+9b2=9b2−24b+16

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

(a−b)3=(a−b)(a−b)(a−b)=(a2−ab−ab+b2)(a−b)=(a2−2ab+b2)(a−b)=a3−2a2b+ab2−a2b+2ab2−b3=a3+(−2a2b−a2b)+(ab2+2ab2)−b3=a3−3a2b+3ab2−b3