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Urgent help

Please help me with these two questions

1. Find vaalues of the constants AmB and C in identity
4x2 - 18x +29 = A(x-4)2 - B (x-2) + C

2. The equation x2 + 3px + p = 0, where p is a non-zero constant and has equal roots. Find the value of p.
Original post by AB J
Please help me with these two questions

1. Find vaalues of the constants AmB and C in identity
4x2 - 18x +29 = A(x-4)2 - B (x-2) + C

2. The equation x2 + 3px + p = 0, where p is a non-zero constant and has equal roots. Find the value of p.


What have you tried so far? If you are stuck right at the start, for (1) expand out the right hand side and then think. For (2) expand (xa)2(x-a)^2 and then think.
Reply 2
Original post by Gregorius
What have you tried so far? If you are stuck right at the start, for (1) expand out the right hand side and then think. For (2) expand (xa)2(x-a)^2 and then think.


I have done 1st question. Thanks for your reply. But still stuck on 2.
Original post by AB J
I have done 1st question. Thanks for your reply. But still stuck on 2.


equal roots means the discriminant = 0

thus b²-4ac=0
I'm sure you can work out the rest ^-^
Original post by AB J
I have done 1st question. Thanks for your reply. But still stuck on 2.


(xa)2=x22ax+a2=x2+3px+p(x-a)^2 = x^2 - 2 a x + a^2 = x^2 + 3 p x + p

So you know that a2=pa^2 = p and 3p=2a/33p = -2a/3. Now solve (observing that there is one solution staring you in the face!)

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