Please help me understand an exam question I had last semester. I know how to find the solution if I could use but I wasn't allowed to use that method and with completing the square, I would normally put the equation in unity, but it already is so I can miss that step, then take half the coefficients of the b term, move the constant to the other side of the equation, take half the coefficient of b and put it in a bracket, expand the bracket out to see what I need to add or subtract from the equation and bob should be my uncle, but I cant find the solution!
Right the questions was:
(i) By completing the square, find in terms of k the roots of the equation
Any help would be greatly appreciated!
Do you know how to multiply polynomials? In particular do you know that ? If so compare that with the your expression:
and You need to get and get rid of -7. You can do that by adding [itex]k^2[/itex] and 7 to both sides of the equation.