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IF F(x)=2x^3+Ax^2+4X-5 andf(2)=5 then find A?​

1 Answer

4 votes

Answer:


\huge\boxed{\sf A = -7/2}

Explanation:

Given function is:


\sf f(x) = 2x^3+Ax^2 + 4x-5


\rule[225]{225}{2}

Put x = 2


\sf f(2) = 2(2)^3+A(2)^2+4(2)-5\\\\f(2) = 2(8) + A(4)+8-5\\\\f(2) = 16 + 4A+3\\\\f(2) = 4A+19\\\\Given \ that \ f(2) = 5\\\\So,\\\\5 = 4A + 19\\\\Subtracting \ 19 \ to \ both \ sides\\\\5-19 = 4A\\\\-14 = 4A\\\\Dividing\ both\ sides\ by\ 4\\\\A = -14 / 4\\\\A = -7/2


\rule[225]{225}{2}

Hope this helped!

~AnonymousHelper1807

User Alexander Hein
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