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Answer :

Given:

[tex]\begin{gathered} r=\sin\theta+5\cos\theta \\ \theta=\frac{\pi}{2} \end{gathered}[/tex]

To find: The slope of the tangent line

Explanation:

Let us take,

[tex]\begin{gathered} x=r\cos\theta \\ y=r\sin\theta \end{gathered}[/tex]

Substituting the r-value in the above equations, we get,

[tex]x=(\sin\theta+5\cos\theta)\cos\theta[/tex]

Differentiating using the product rule,

[tex]\begin{gathered} \frac{dx}{d\theta}=(\sin\theta+5\cos\theta)(-\sin\theta)+\cos\theta(\cos\theta-5\sin\theta) \\ =-\sin^2\theta-5\sin\theta\cos\theta+\cos^2\theta-5\sin\theta\cos\theta \\ =\cos^2\theta-\sin^2\theta..........(1) \end{gathered}[/tex]

And we have,

[tex]y=(\sin\theta+5\cos\theta)\sin\theta[/tex]

Differentiating using the product rule,

[tex]\begin{gathered} \frac{dy}{d\theta}=(\sin\theta+5\cos\theta)(cos\theta)+\sin\theta(\cos\theta-5\sin\theta) \\ =\sin\theta\cos\theta+5\cos^2\theta+\sin\theta\cos\theta-5\sin^2\theta \\ =2\sin\theta\cos\theta+5(\cos^2\theta-\sin^2\theta)..........(2) \end{gathered}[/tex]

Dividing equation (2) by (1), we get

[tex]\begin{gathered} \frac{dy}{dx}=\frac{\frac{dy}{d\theta}}{\frac{dx}{d\theta}} \\ =\frac{2\sin\theta\cos\theta+5(\cos^2\theta-\sin^2\theta)}{\cos^2\theta-sin^2\theta} \end{gathered}[/tex]

The slope of the tangent line at the given angle is,

[tex]\begin{gathered} [\frac{dy}{dx}]_{\frac{\pi}{2}}=\frac{2(1)(0)+5(0-1)}{0-1} \\ =-\frac{5}{-1} \\ =5 \end{gathered}[/tex]

Final answer:

The slope of the tangent line to the given polar curve at the point specified by the value of θ is 5.