How do you factor #x^4-9x^2+18#?
After this you can factorise for t:
So factorisation for t would be:
Now, we have to find x; in order to do that, we have to find the roots of t's. Since this is a quadratic equation it has to be equal zero, so:
Let's find x1 and x2:
To get the correct answers we have to find which of the four roots fits into the equation to satisfy it to be zero.
First, let's try with the first one:
So the solutions are: