## If cos 'theta' =1/2 the sin'theta' = WHAT?

Trigonometric ratios and functions, the unit circle, inverse trig functions, identities, trig graphs, etc.
rere
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### If cos 'theta' =1/2 the sin'theta' = WHAT?

If 90 degrees < 'theta' <180 degrees what is equaled to 5 cos 'theta' sec 'theta'?

and another...

If cos 'theta' =1/2 the sin'theta' = WHAT?

thank you for any advice and help.

stapel_eliz
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Joined: Mon Dec 08, 2008 4:22 pm
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If 90 degrees < 'theta' <180 degrees what is equaled to 5 cos 'theta' sec 'theta'?
I'm sorry, but I don't understand what this exercise is asking...? Are you supposed to find a range of value for the product of the 5, the cosine, and the secant? Or something else?
If cos 'theta' =1/2 the sin'theta' = WHAT?
Draw the right triangle. Label "adjacent" and "hypotenuse" sides with the values from the cosine ratio. Use the Pythagorean Theorem to find the value for the "opposite" side. Read off the value of the sine from the picture.

rere
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Joined: Thu Jul 23, 2009 11:51 pm
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### Re: If cos 'theta' =1/2 the sin'theta' = WHAT?

Yes, I am not sure what the question is asking for, I wrote it just as the problem said...Perhaps it is a typo
If f9x0=x^2-x, which of the following is equal to x^2+x
A. f(x)+x
B. f(x)-x
C. -f(x)
D. f(-x)
E. [f(x)]^2
Thanks

stapel_eliz
Posts: 1628
Joined: Mon Dec 08, 2008 4:22 pm
Contact:
If f9x0=x^2-x, which of the following is equal to x^2+x
I will guess that the first bit is supposed to be $f(x)\, =\, x^2\, -\, x.$

If so, try plugging $x^2\, -\, x$ into the various expressions, in places of $f(x)$, and find the one that matches.