How do you find an equation of the tangent line to the curve at the given point: y = csc (x) - 2 sin (x) and P = (pi/6, 1)?

1 Answer
Nov 15, 2016

The equation is y = -3sqrt(3)x + (pisqrt(3) + 1)/2

Explanation:

Start by differentiating the function.

y= 1/sinx - 2sinx

dy/dx= (0 xx sinx - cosx xx 1)/(sinx)^2 - 2cosx

dy/dx= -cosx/sin^2x - 2cosx

dy/dx = -cotxcscx - 2cosx

Now, find the slope of the tangent.

dy/dx = -cot(pi/6)csc(pi/6) - 2cos(pi/6)

dy/dx = -1/tan(pi/6) xx 1/sin(pi/6) - 2cos(pi/6)

dy/dx = -1/(1/sqrt(3)) xx 1/(1/2) - 2(sqrt(3)/2)

dy/dx= -sqrt(3) xx 2 - sqrt(3)

dy/dx = -2sqrt(3) - sqrt(3)

dy/dx= -3sqrt(3)

We now find the equation of the tangent line with our point and our slope.

y_ y_1 = m(x- x_1)

y - 1 = -3sqrt(3)(x - pi/6)

y - 1 = -3sqrt(3)x + (pisqrt(3))/2

y = -3sqrt(3)x + (pisqrt(3))/2 + 1

y = -3sqrt(3)x + (pisqrt(3) + 1)/2

Hopefully this helps!