teht. 335

a)x^3+7=132x^3=132-7x^3=125x=\sqrt[3]{125}=5

c)x^4-5=-86x^4=-86+5x^4=-81Eiratkaisua
b)-2x^6=-1458x^6=\frac{-1458}{-2}x^6=729x=\sqrt[6]{729}x=3\ tai\ x=-3