calculus problem help

giuly

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i need help finding the line that is tangent to the curve y=sin(3?x/2) at x = 4, im not sure on how to start the problem. If someone could help me i would really appreciate it.
 
giuly said:
i need help finding the line that is tangent to the curve y=sin(3?x/2) at x = 4, im not sure on how to start the problem. If someone could help me i would really appreciate it.

The slope of the tangent line = y'(4)

The tangent line passes through (4,y(4))

What is the point-slope form of equation of a line?

And you have it ......
 
f(x) = sin(3πx2) at x =4, y = 0.\displaystyle f(x) \ = \ sin\bigg(\frac{3\pi x}{2}\bigg) \ at \ x \ =4, \ y \ = \ 0.

f  (x) = 3π2cos(3πx2).\displaystyle f \ ' \ (x) \ = \ \frac{3\pi}{2}cos\bigg(\frac{3\pi x}{2}\bigg).

f  (4) = 3π2 = m\displaystyle f \ ' \ (4) \ = \ \frac{3\pi}{2} \ = \ m

Ergo, y0 = 3π2(x4) = 3πx26π\displaystyle Ergo, \ y-0 \ = \ \frac{3\pi}{2}(x-4) \ = \ \frac{3\pi x}{2}-6\pi

See graph below.\displaystyle See \ graph \ below.

[attachment=0:r0ig6zqg]xyz.jpg[/attachment:r0ig6zqg]
 

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