Question

factor 3x^4-12x^2

Answer 1

Solved it, thanks

Answer 2

Try to see what the common factors are. Do this by writing out all of them:\[3x^4-12x^2=3\cdot x\cdot x\cdot x\cdot x-2 \cdot2\cdot3\cdot x\cdot x\]
All you have to do now is put the common factors before the brackets, the rest in between...