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I need help in maths !!1

janajedii

ok im just gnna type it out,
" find the value of p for which the quadratic equation px^2-4px+2-p=0 has equal roots "
ty

Reply 1

Kevin De Bruyne

Original post by janajedii

ok im just gnna type it out,
" find the value of p for which the quadratic equation px^2-4px+2-p=0 has equal roots "
ty

Okay, what is your gut reaction when it says 'equal roots'? What do you need to do?

Reply 2

Dysf(x)al

Original post by janajedii

ok im just gnna type it out,
" find the value of p for which the quadratic equation px^2-4px+2-p=0 has equal roots "
ty

When there are equal roots (sometimes called "repeated roots"), what is the discriminant (b^2 - 4ac) equal to?

Reply 3

janajedii

Original post by TheMindGarage

When there are equal roots (sometimes called "repeated roots" :wink:

, what is the discriminant (b^2 - 4ac) equal to?

0 innit

Reply 4

Dysf(x)al

Original post by janajedii

0 innit

Correct! So, the original equation was px^2-4px+2-p=0. This means that using the usual quadratic format, a = p, b = 4p and c = 2-p. Substitute this into b^2 - 4ac = 0, you get (4p)^2 - 4p(2-p) = 0. Expand this out and you have a quadratic - be careful to realise that (4p)^2 equals 16p^2 and not 4p^2! You should get two solutions when solving it, but make sure both of them make sense!