Nickirusso
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Let f(x)=10x+14−15e^(x) Then the equation of the tangent line to the graph of f(x) at the point (0,−1) is given by y=mx+b for
M = ???
B = -1
M = ???
B = -1
tangent line
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Otis
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Hi Nickirusso. Please use the given symbols m and b (capital letters are different symbols).
m = the slope of the tangent line
The first derivative of function f outputs the slope of the tangent line at x. Please show us your attempt at finding the first derivative of f(x).
b = -1 is correct. Very good reasoning.
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Nickirusso
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The equation that I have done to find m Is
10(0) - 15e ^(0) and I get - 15 and I firmly believe that this is the correct slope but it appears that the answer of -15 is incorrect. Thank you for your reply!
Dr.Peterson
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It looks like you are just finding f(0) and dropping the constant term. That is not how you find the slope.
The slope of the tangent line, as you have been reminded, is the derivative of the function. So you need to find f'(0), and that will be the m to use in the equation of the tangent line.
Otis
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Hi Nickirusso. That is not an equation. (All equations contain an equals sign.) We call that an 'expression'.
You didn't show your attempt at finding the first derivative, so I have to guess what you're thinking. Is this guess correct, for what you think?
f´(x) = 10x - e^x
If so, then you're close. Please check your work, to see if you can find the mistake.
If you can't find the mistake, then look up the 'Power Rule' for derivatives.
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