Question

Solve: 125x^3 + 343=0
Find all Complex Roots.

Answer 1

`125x^3+343=0 \\(5x)^3+7^3=0 \\(5x+7)(25x^2-35x+49)=0 \\25x^2-35x+49=0 \\a=25,b=-35,c=49 \\ \\x_(1,2)= (-(-35)\pm √((-35)^2-4*25*49) )/(2*25)=(35\pm √(-3675) )/(50)=(35\pm i√(3675) )/(50)`