Question

4x²+7x+7x+3=0 уровнейе​

Answer 1

Ответ:

$x_1=\displaystyle\frac{-7-\sqrt{37} }{4} ~;~x_2=\frac{-7+\sqrt{37} }{4} .$

Объяснение:

$4x^2+7x+7x+3=0\\4x^2+14x+3=0\\a=1;b=14;c=3\\D=b^2-4ac=14^2-4*4*3=148\\\sqrt{D} =\sqrt{148} =\sqrt{4*37} =2\sqrt{37} \\x_1=\displaystyle\frac{-b-\sqrt{D} }{2a} =\frac{-14-2\sqrt{37} }{2*4} =\frac{\not2(-7-\sqrt{37} )}{\not2*4} =\bf \frac{-7-\sqrt{37} }{4} \\x_2=\displaystyle\frac{-b+\sqrt{D} }{2a} =\frac{-14+2\sqrt{37} }{2*4} =\frac{\not2(-7+\sqrt{37} )}{\not2*4} =\bf \frac{-7+\sqrt{37} }{4}$