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# Calculus/Cal 1

Question
Find f"(x) for the function.

f(x)= x^2+√x

A. 2x^(3/2)+1/x^(3/2)
B. 8x^(3/2)-1/4x^(3/2)
C. 2x^(3/2)-1/x^(3/2)
D. 8x^(3/2)+1/4x^(3/2)

It is none of the above.  When differentiation a function (powers of x), its degree should go down by 1.  So taking the second derivative will decrease the degree by two.  Your function f, is made up of the sum of a function whose degree is two (first function) and a function who degree is half (second function).

After two derivative, the first function will have degree zero.  That would be a constant function.  Similarly, after two derivatives, the second function will have degree half minus two which is negative three halves (or -1.5).  And none of the choices above is a constant plus a function of degree minus three halves.

The correct answer should be 2 - 1/(4x^1.5).

Calculus

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#### Amos

##### Expertise

I can answer all calculus question. I am a Math Lecturer and I teach Math in a College, usually Calculus 1, Calculus 2 and Calculus 3 and Linear Algebra.

##### Experience

I have been teaching in this college for more than 12 years. Prior to that, I taught for three years as Visiting Assistant Professor.

Education/Credentials
I got my doctorate from Univ. of Rochester in Algebraic Toppology. I got a MA from Univ of Rochester, an MA from York Univ. in Toronto and almost did my M.Sc in the National Univ. of Singapore.