Question 245178
Find the approxmiate value of the tangent to the following functions at the given x-value. Use the algebraic method. 
A) y = 1/x at x = 1
y' = -1/x^2 which is the equation of the tangent.
@ x = 1, y' = -1 which is the slope of the tangent.
You said "value of the tangent", I'm not sure what that is.
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B) y = 3cos3x at x = 3 
y' = -9sin(3x)
at x = 3, y' = -9sin(9)
=~ -3.709066
I assumed x is in radians.  If not, it will have to be converted before the function is differentiated.
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I don't know what the "algebraic method" is.  You can use this info to check your answers, if nothing else.