Find the slope of the tangent line to the given polar curve at the point specified by the value of θ.
r = 6sin(θ)
θ = π/3
I attempted this and got the answers 0 and .36397 but both were incorrect. If anyone knows how to do this please help me out and show how you can arrive at the answer. Thanks in advance!
r = 6sin(θ)
θ = π/3
I attempted this and got the answers 0 and .36397 but both were incorrect. If anyone knows how to do this please help me out and show how you can arrive at the answer. Thanks in advance!
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Maybe this will help:
In order to find the slope of the tangent line for use in a linear equation you need to know the derivative in terms of y and x. You would need to know dy/dx. Remember that you can treat this derivative as a ratio of change in y over change in x:
dy/dx = [dy/dθ] / [dx/dθ]
So you must know the conversion form polar to rectangular coordinates, which you probably do:
x=rcosθ
y=rsinθ
r is given as 6sinθ
x=6sinθcosθ (this is actually just 3sin2θ)
y=6sin^2θ
Now you can find dy/dθ and dx/dθ:
dy/dθ = 12sinθcosθ = 6sin2θ
dx/dθ = 6cos2θ
Now dy/dx = dy/dθ / dx/dθ = (6sin2θ) / (6cos2θ) = tan2θ
tan(2*π/3) = - sqrt(3)
which is approximately equal to -1.7321.
If you look at the graph of this function you would know that the slope would have to be negative at θ= π/3.
In order to find the slope of the tangent line for use in a linear equation you need to know the derivative in terms of y and x. You would need to know dy/dx. Remember that you can treat this derivative as a ratio of change in y over change in x:
dy/dx = [dy/dθ] / [dx/dθ]
So you must know the conversion form polar to rectangular coordinates, which you probably do:
x=rcosθ
y=rsinθ
r is given as 6sinθ
x=6sinθcosθ (this is actually just 3sin2θ)
y=6sin^2θ
Now you can find dy/dθ and dx/dθ:
dy/dθ = 12sinθcosθ = 6sin2θ
dx/dθ = 6cos2θ
Now dy/dx = dy/dθ / dx/dθ = (6sin2θ) / (6cos2θ) = tan2θ
tan(2*π/3) = - sqrt(3)
which is approximately equal to -1.7321.
If you look at the graph of this function you would know that the slope would have to be negative at θ= π/3.