Can i get some help with this, Please? Given cos theta=24/25 and is located in Q3, Evaluate the rest of the trigonometric functions: 1. sin theta= 2. tan theta= 3. cot theta= 4. sec theta= 5. csc theta=
sin^2 + cos^2 = 1 sin^2 + (24/25)^2 = 1 sin^2 + 576/625 = 1 sin^2 = 1 - 576/625 sin^2 = 49/625 sin = sqrt(49/625) sin = 7/25 Since we're in Q3, sine theta is negative, so sin theta = -7/25 So when cos theta=24/25, sin theta = -7/25
eh, that looks confusing. So for tan theta, would i start off as tan^2+cos^2
tan = sin/cos
that's one of the definitions of tangent
oh yeah, i remember that. So what do i do next?
tan = sin/cos tan = (-7/25)/(-24/25) tan = (-7/25)*(-25/24) tan = 7/24 Note: cosine should be negative as well in Q3...not sure why they made it positive
So is there a reason why you swapped (-24/25) to (-25/24) or does it matter?
(a/b) divided by (c/d) is the same as (a/b) times (d/c)
when you divide fractions, flip the second fraction and multiply
Oh ok. So im a little familiar with tan, cos, and sin. But not with cot,csc, and sec.
cot = 1/tan csc = 1/sin sec = 1/cos all by definition
so if tan = a/b, then cot = b/a (you flip the fraction...ie find the reciprocal) In this case, tan = 7/24 so cot = 24/7
so times cot by cos?
no, you take whatever tan is and you flip it to get cot
oh, pretty easy.
yeah it's not too bad once you get the hang of it
the trick is remembering what cot, csc and sec stand for (and what they equal)
so sec=1/cos so sec=1/(24/25)?
yes, but cosine should be negative
so sec = 1/(-24/25) ----> sec = -25/24
and the last one is csc theta= what does csc even mean? Like tan=tangent.
cot = cotangent csc = cosecant sec = secant
So for csc... 1/(-7/25) ?
yes, which becomes csc = -25/7
Your so much help. Thank you so so much.
you're very welcome
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