Question

Обчислити зручним способом: 15 во 2 степени + 2 ∙ 15 ∙ 35 + 35 во 2 степени​

Answer 1

$\displaystyle15^2+2\cdot15\cdot35+35^2=(15+35)^2=50^2=2500$

Answer 2

$(2 \times 35 \times 15) + ( {15}^{2} + {35}^{2} ) = 2 \times 5(7 + 3) + {5}^{2} (7 + 3) = (7 + 3)(2 \times 5 + {5}^{2} ) = 10 \times 250 = 2500$