Year 12s: what will be the first way you research your future options? >>

simple q

Hectorious

I can do the rest, but I don't understand why a) is -2 and 2.

Reply 1

the bear

you can factorize the curve equation further because you have the difference of two squares...

Reply 2

Extricated

y = (x-1)(x^2-4) so when y = 0, x = 1, and x^2-4 = 0....... we already have p which is 1,0. So we only need to solve x^2-4 = 0. Note that when you find x you will have a positive and negative.

Reply 3

f1mad

y=0

-> (x-1) or (x^2-4)=0 Yes?

x=1 or x^2=4-> x= +/-2

Now you already know it crosses the x axis at 1 already, so Q must be +2. Similarly P is negative and also crosses the x axis when y=0 so P must be -2.