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If tan theta =8 /15, evaluate sin theta +cos theta /cos theta (1-cos theta)​

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Answer:

Therefore,

(sin theta + cos theta) / [cos theta (1 - cos theta)] = sec theta + csc theta

= [sqrt(1 - cos^2 theta) + cos theta] / [cos theta (1 - cos theta)]

Explanation:

We know that:

tan theta = sin theta / cos theta

Using this, we can say:

8/15 = sin theta / cos theta

We also know that:

sin^2 theta + cos^2 theta = 1

Rearranging, we get:

sin^2 theta = 1 - cos^2 theta

Taking the square root, we get:

sin theta = sqrt(1 - cos^2 theta)

Putting the value of sin theta in terms of cos theta in the given expression, we get:

(sin theta + cos theta) / [cos theta (1 - cos theta)]

= [sqrt(1 - cos^2 theta) + cos theta] / [cos theta (1 - cos theta)]

= [sqrt(1 - cos^2 theta) / cos theta] + 1 / (1 - cos theta)

= sec theta + csc theta

Now, we need to find the value of sec theta and csc theta in terms of cos theta. We know that:

sec theta = 1 / cos theta

csc theta = 1 / sin theta

= 1 / sqrt(1 - cos^2 theta)

Substituting these values in the expression we derived earlier, we get:

(sec theta + csc theta) = 1/cos theta + 1/ sqrt(1 - cos^2 theta)

= [sqrt(1 - cos^2 theta) + cos theta] / [cos theta (1 - cos theta)]

User Thomas Clayson
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