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Sine rule using radians

So I have a triangle with angle 0.5 rad and sides 7cm and 8cm and I'm trying to use the sine rule to find angle x (i.e. 0.5/7 = x/8) but I keep getting the wrong answer, I'm just subbing the numbers in to the formula. Do I need to have my calculator in rad mode or convert to degrees then back to radians or what? Thanks! ;/

Reply 1

ScrumpyMax

You need to use the sine of the angle, not just the angle

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Reply 2

Hasufel

is your answer 0.43 rads (approx 24 deg)? - depends which side is opposite which angle...

if your calc is in degrres, just multiply your answer by 180/Pi

remember a/sina = b/sinb

Reply 3

white_o

Original post by ScrumpyMax

You need to use the sine of the angle, not just the angle

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Omg I completely forgot -____- thanks so much hahaa

Reply 4

ScrumpyMax

The clue's in the name :wink:

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Reply 5

white_o

Original post by ScrumpyMax

The clue's in the name :wink:

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Hahaha good point >.< and btw, if I'm trying to find the second possible value for x, do I just do pi-the first value? Or is there a different way of finding the two possible values?

Reply 6

ScrumpyMax

Yeah, the three angles sum to pi

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Reply 7

TenOfThem

Original post by Qaiys

Hahaha good point >.< and btw, if I'm trying to find the second possible value for x, do I just do pi-the first value? Or is there a different way of finding the two possible values?