# maths

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If the ratio of the roots of the quadratic equation ax^2 + bx +c =0 is m:n
prove that mnb^2=(m+n)^2 ac

• maths -

sum: m + n = -b/a
product: mn = c/a
substitute. when proving, you only manipulate/solve one side.
mnb^2=(m+n)^2 ac
(c/a)(b^2) =? (ac)(m+n)^2
(c/a)[a(m + n)]^2 =? (ac)(m+n)^2
(c/a)(a^2)(m+n)^2 =? (ac)(m+n)^2
(ac)(m+n)^2 = (ac)(m+n)^2
this problem is pretty much the same as the one you posted earlier. you should also check Naruto's answer on that post.

• maths -

Gee! Naruto and Sasuke seem to be the same person!!

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