F(x)=x^3+x^2-42x
Roots
Solve for x over the real numbers
x³+x²-42x=0
Factor the left-hand side
The left-hand side factors into a product with three terms
x(x-6)(x+7)=0
Find the roots of each term separately
Split into three equations
x-6=0 x=0 x+7=0
Look at the first equation and solve for x
Add 6 to both sides
x=6 x=0 x+7=0
Look at the third equation and solve for x
Subtract 7 from both sides
Answer:
x=6 x=0 x=-7