Question

помогите решить
2) 36c2 + 6cd + 0,25d2
4) 1/49a² + 2/21ab+1/9b2
6)81d2-27/2cd+9/16c2​

Answer 1

2) 36c² + 6cd + 0,25d²=(6c+0.5d)²

4) (1/49)a² + (2/21)ab+1/9b²=((а/7)+(b/3))²

6)81d²-(27/2)cd+(9/16)c²​=(9d-(3/4)c)²

Answer 2

Ответ:

$2)\ \ 36c^2+6cd+0,25d^2=(6c)^2+2\cdot 6c+0,5d+(0,5d)^2=(6c+0,5d)^2\\\\\\4)\ \ \dfrac{1}{49}\, a^2+\dfrac{2}{21}\, ab+\dfrac{1}{9}\, b^2=\Big(\dfrac{1}{7}\, a\Bg)^2+2\cdot \dfrac{1}{7}\, a\cdot \dfrac{1}{3}\, b+\Big(\dfrac{1}{3}\, b\Big)^2=\Big(\dfrac{1}{7}\, a+ \dfrac{1}{3}\, b\Big)^2\\\\\\6)\ \ 81d^2-\dfrac{27}{2}\, cd+\dfrac{9}{16}\, c^2=\Big(9d\Big)^2-2\cdot 9d\cdot \dfrac{3}{4}\, c+\Big(\dfrac{3}{4}c\Big)^2=\Big(9d-\dfrac{3}{4}\, c\Big)^2$