I've got a question and my answer has revealed that I've got the wrong idea.
'Determine the two pints on the curve with equation y=(x2+3)(x−5) where the gradient is equal to -5.
So this is what I did. I simplified the equation, differentiated it, then carried -5 over to the other side so I had a quadratic. I could factorise it so I put it through the quadratic equation. This must have been the wrong thing to do though as the answer is wrong
I've got a question and my answer has revealed that I've got the wrong idea.
'Determine the two pints on the curve with equation y=(x2+3)(x−5) where the gradient is equal to -5.
So this is what I did. I simplified the equation, differentiated it, then carried -5 over to the other side so I had a quadratic. I could factorise it so I put it through the quadratic equation. This must have been the wrong thing to do though as the answer is wrong
Is this right?
y=(x2+3)(x−5) = y=x3−5x2+3x−15 dxdy=3x2−10x+3 when dxdy=−5 then 3x2−10x+8=0 which equals (3x−4)(x−2) so x=34or2
Just talking out of experience. He might learn that way too.
You look to be very experienced, can you give more advice on preparing maths?
If someone follows your advice for A-Level maths, and then if he has to give STEP/AEA, than what shall he do to prepare? Learn all the STEP/AEA mark schemes?