Melody

(y+4) (y-2)

=y (y-2)   +4(y-2)

= y^2   -2y     +4y    -8

= y^2     +  2y         -8

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Thanks Alan. :)

Use the reference angle to find the exact value of tan ( - 11pi/4 )

\(\frac{-11\pi}{4}=\frac{-8\pi}{4}-\frac{3\pi}{4}=\frac{-3\pi}{4}=\frac{-3\pi}{4}+\frac{8\pi}{4}=\frac{5\pi}{4}=\pi+\frac{\pi}{4}\\ tan(\pi+\frac{\pi}{4})=tan(\frac{\pi}{4})=1\)

What's the exact value of csc theta given the following point on the terminal side of angle theta : (-5, 7)

\(cosec\;\theta=\frac{1}{sin\;\theta} = \frac{hyp}{opp} = \frac{\sqrt{74}}{7}\)

Evaluate COS 3pi/2

cos 270 degrees = x value on  the unit circle = 0

The original angle was in radians but the answer is just 0    There are no units it is just a number.

Evaluate CSC 3pi/2

cosec 270 = 1/sin 270 

The y value on the unit circle is -1 at 270 degress

= 1/-1 = -1

Find the exact value of tan theta given that sin theta = -15/17 and theta is in Quadrant III

3rd quad so will be tan be pos or neg?   

Draw a right angeld triangle.

theta is one of the acute angles.

put 15 an 17 on two sides to make sin theta=15/17 true

Find the third side using Pythagoras

Read tan theta off the triangle.  Make sue you add the plus or the minus as needed.

Which quad will give negative tan values?

Which quad give pos cos values.?

Which quadrant will be true for both. ?

This calculator was programmed and developed by just one brilliant German programmer.

His name is Andre Massow and he is the owner of this site. 

Thank you Dragonlance (or should I call you John Boy now)   for sharing your narative with us. 

I thought it was really sweet.

I am really glad that you have learned from us and that you enjoy being a member of our little community.