Question

(2a + 1)^2 + 2(2a + 1)(a - 1) + (a - 1)^2 при а = - 3,5
срочно плизз​

Answer 1

$\left ( 2a+1 \right )^2+2\left ( 2a+1 \right )\left ( a-1 \right )+\left ( a-1 \right )^2\\\left ( 2a+1+a-1 \right )^2=9a^2\\a=-3,5\Rightarrow 9\cdot \left ( \frac{7}{2} \right )^2=9\cdot \frac{49}{4}=\frac{441}{4}$