Question

Решить уравнение: sqrt( 4 x +12)+sqrt(12-8x)=sqrt(28+8x)

Answer 1

$sqrt{4x+12}+sqrt{12-8x}=sqrt{28+8x}\ sqrt{4x+12}+sqrt{-2(4x+12)+36}=sqrt{2(4x+12)+4}\ 4x+12=u \\ sqrt{u}+sqrt{-2u+36}=sqrt{2u+4}\ sqrt{36-2u}=sqrt{2u+4}-sqrt{u}\ 36-2u=2u+4-2sqrt{u(2u+4)}+u\ 32-5u=-2sqrt{2u^2+4u}\ 32^2-320u+25u^2=4(2u^2+4u) u=frac{64}{17};\u=16\ x=-frac{35}{17}\ x=1$
первый не подходит ответ $x=1$