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Hard questions

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

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.

Expansion may help you can see what A is going to be anyway, because there's only one x^2 term on the RHS.

For 2, if you are given that a quadratic has equal roots.. what calculation can you perform?
Reply 2
Original post by SeanFM
Expansion may help you can see what A is going to be anyway, because there's only one x^2 term on the RHS.

For 2, if you are given that a quadratic has equal roots.. what calculation can you perform?


We can find discriminant. If discriminant is zero there are 2 roots that are equal.
Original post by AB J
We can find discriminant. If discriminant is zero there are 2 roots that are equal.


Correct :h: so can you find p now?

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