tan(theta)=−3/4 and cos(theta)>0. Find sin(theta), cos(theta), cot(theta), csc(theta), and sec(theta).
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find the hypotenuse by pythagoras or memory then take the appropriate ratios, being mindful of what quadrant you are in so you can put the right sign \(+\) or \(-1\) in your answer
It says cos(theta)>0 So..it must be in 4th quadrant
That's what I don't understand. How do I know which quadrant I am in when cos theta is > 0?
OH. Okay. Let me try :)
forget about the signs until the answer sides of a triangle are positive you are in quadrant 4 because cosine in positive but sine is negative.
from the picture we see cosine is \(\frac{3}{5}\) and you know it is positive because you are told
oops i mean cosine is \(\frac{4}{5}\) sorry
sine is \(-\frac{3}{5}\) you get the \(\frac{3}{5}\) from the triangle, and it is negative because you are in quadrant 4 etc
OH i get it okay. one second. THANK YOU!
so sin = -3/5; cos = 4/5; cot 4/3; csc -4/5; sec 5/4?
cot = -4/3**
Yup....
your cosecant is wrong, all others are right
Sec and Cos are only +ve..
and the cotangent
oh you corrected it
cosec = 1/ sin x
cosec x = -5/3
I got: sin -3/5; cos 4/5; cot -4/3; csc -5/3; sec 5/4 correct?
thank you!
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