Equation of Tangent Line to y=(lnx)^cosx at (pi/2,1)

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To find the equation of the tangent line to the curve y=(lnx)^cosx at the point (π/2, 1), the derivative y' must be calculated using implicit differentiation. The expression for y' is derived as y' = y[-sin(x)ln(ln(x)) + cos(x)/(ln(x)x)]. At x=π/2, the slope of the tangent line can be determined by substituting π/2 into the derivative. Finally, the y-intercept can be calculated to ensure the tangent line passes through the point (π/2, 1). This process leads to the complete equation of the tangent line.
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Find the equation of the tangent line to the curve y=(lnx)^cosx at the point (pi/2, 1)?

The Attempt at a Solution


lny = cosx(ln(ln(x))) d/dx
= -sinx(ln(ln(x))) + cosx/(ln(x)(x))
y' = y(-sinx(ln(ln(x))) + cosx/(ln(x)(x)))
this is the part where I get stuck
 
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dvaughn said:
Find the equation of the tangent line to the curve y=(lnx)^cosx at the point (pi/2, 1)?

The Attempt at a Solution


lny = cosx(ln(ln(x))) d/dx
= -sinx(ln(ln(x))) + cosx/(ln(x)(x))
y' = y(-sinx(ln(ln(x))) + cosx/(ln(x)(x)))
this is the part where I get stuck

When you get to
y'=y\left[ {\frac{\cos\left(x\right)}{x\ln\left(x\right)}-\sin\left(x\right)\ln\left(\ln\left(x\right)\right)}\right]
substitute \ln\left(x\right)^{\cos\left(x\right)} for y.

Then take y'\left(\frac{\pi}{2}\right) as the slope of your tangent line and find what y-intercept will put the line through \left(\frac{\pi}{2},1\right).
 
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