SOLUTION: Use the information given about angle theta to find the exact value of cosine theta/2 sin theta=3/5 and 0<theta<pie/2

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Question 516629: Use the information given about angle theta to find the exact value of cosine theta/2
sin theta=3/5 and 0
Answer by solver91311(24713) (Show Source):
You can put this solution on YOUR website!

First use the Pythagorean Identity to find .

But recall , hence is a 1st quadrant angle, therefore the cosine is positive.

Now use the half angle formula for cosine:

But recall , hence , is also a 1st quadrant angle, therefore the cosine is positive.

After rationalizing the denominator. One last thing: pie is dessert, pi is the lower case Greek letter denoting the ratio between the circumference and the diameter of a circle.

John

My calculator said it, I believe it, that settles it