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# Differentiate

1. Consider the function f(x)=(&#8722;5x^(2))+7x+15.

a) For the given function f, the expression f(x+h)-f(x)/h can be simplified to the form Ax+Bh+C, where A, B and C are constants. Do it.

b) Using the result of (a), find the derivative of f at x .
Answer: f'(x)=______. Note. The correct answer should be an expression in x.

c) Suppose that the position of a particle at time t is given by s=&#8722;5t^(2)+7t+15. What is the particle's instantaneous velocity at time t=2?
Answer: The particle's instantaneous velocity at time t=2 is _____

2. Differentiate the given functions. For this question, you may use the following differentiation rules and formulas:
If r is any rational number, then d/dx (x^r)=rx^(r-1).
If f and g are differentiable functions of x, and if &#945; and &#946; are constants, then
d/dx (&#945;f(x)+&#946;g(x))= &#945; d/dx (f(x))+&#946; d/dx (g(x)).

In each case, state the domain of the derivative.
a) f(x)=&#8722;3x^(3)&#8722;1x^(2)&#8722;4x+1.
Answer: The derivative of f(x) is f'(x)=______, and the domain of f' is ______

b)f(x)=5x^(3/2)-2x^(1/2)-1x^(-1/2)-4x^(-3/2).
Answer: The derivative of f(x) is f'(x)=_____, and the domain of f' is _____

c) f(x)=-3sqrt(x)+2/sqrt(x)+2/x+_3/x^(2).
Answer: The derivative of f(x) is f'(x)=______, and the domain of f' is ______

3. Differentiate the following functions and simplify your answers into the specified form.

a) f(x)=-1x-7/-10x^(2)-7.

b) g(x)=x^(3)/-9x+6

4. Differentiate the following functions and simplify your answers into the specified form.

a) f(x)=(12x&#8722;8)sinx+(&#8722;7x&#8722;5)cosx.