Equation of tangent line
for an equation of a tangent line you need two things.......a point and the slope
I have the slope already right? So I'm supposed to find at what point there is a slope of 1/2?
y' = cosx
1/2 =cos x
x=pi/3
(π/3 , 1/2 ) - your point and the slope 1/2
find b in y=mx+b
Well first, what is the slope of a line? That's right! it is: y = mx + b now what is (m)? that's just the slope, which is just the derivative: y = sin(x) dy/dx = cos(x) now it says you are looking for the point where dy/dx = 1/2, so why don't we go ahead and set 1/2 = cos(x). Now think back to you're trig, what does (x) have to be for cos(x) to be 1/2? Well just think of a 30-60-90 triangle and you should realize x=60 degrees, which is pi/3 1/2 = cos(x) x = pi/3 So now we know use this x-value to find (m) and (b) cos(pi/3) = 1/2 plug (pi/3) back into our original function to get the point we need to write out the line: sin(pi/3) = sqrt(3) / 2 so you're line should now look like this \[y - \sqrt(3) / 2 = (1/2) (x - \pi/3)\] \[y = (1/2) (x - \pi/3) + \sqrt3 / 2\]
You guys are amazing at calculus lol
thanks for medals
^_^
Haha i'm not amazing, I was just like you once, grinding at giga-tons of Calculus homework.
here to help aren't we guys
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