Question

35 баллов!!! ПОМОГИТЕ СРОЧНО

Answer 1

Ответ:

$3)\ \ (3b-5)^2-49=(3b-5)^2-7^2=(3b-5-7)(3b-5+7)=\\\\=(3b-12)(3b+2)\\\\\\a^4-(a-7)^2=(a^2)^2-(a-7)^2=\Big(a^2-(a-7)\Big)\Big(a^2+(a-7)\Big)=\\\\=(a^2-a+7)(a^2+a-7)$

$4)\ \ (2x+3)^2-(x-5)^2=0\\\\\Big(2x+3-(x-5)\Big)\Big(2x+3+(x-5)\Big)=0\\\\(x+8)(3x-2)=0\\\\x+8=0\ \ \to \ \ x_1=-8\\\\3x-2=0\ \ \to \ \ x_2=\dfrac{2}{3}\\\\Otvet:\ \ x_1=-8\ ,\ \ x_2=\dfrac{2}{3}\ .$