Given y=x^3+5x+3 find dy/dx when x=3

The question can be broken into two steps, 

1) dy/dx is asking to differentiate y=x3+5x+3 with respect to x

Differentiating we multiply by the current power and lower this powers value by 1. ( Constants differentiate to nothing )

i.e  x3 goes to 3x2

dy/dx=  3x2+5

2) Next we need to find the value of dy/dx when x=3 done simply by substituting all x's in the equation by 3

dy/dx=  3*(3)+ 5 = 32

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