Inverse Trig (1 Viewer)

Kutay

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Hey everyone i was wondering how you would answer this question, i have just started this topic and wondering for a bit of help!

"Without Caculators or tables evaluate the following:"

sin to -1 ( sin pi/3)
 

KFunk

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It should just be &pi;/3 since sin<sup>-1</sup> undoes sin. Hence sin<sup>-1</sup>(sin&pi;/3) = &pi;/3

EDIT: I thought I should clarify that there are exceptions to sin<sup>-1</sup>(sinx) = x. eg sin<sup>-1</sup>(sin&pi; ) &ne; &pi;. It in fact equals zero (since inverse sin of zero is zero) so look out for when x = n&pi; and n= 0, &plusmn;1 &plusmn;2 etc...
 
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Trev

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I'm not too sure, we did this ages ago, but;
sin^-1[sin.pi/3] = pi/3; as there is the same sine ratio in a sine angle or something, I'm not too sure how to explain it :rolleyes:
 

FinalFantasy

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Trev said:
I'm not too sure, we did this ages ago, but;
sin^-1[sin.pi/3] = pi/3; as there is the same sine ratio in a sine angle or something, I'm not too sure how to explain it :rolleyes:
i think sin^-1 x is the same as "the angle who's sin is x"
so sin^-1[sin.pi/3] would be "the angle who's sin is sin pi\3"
and that's pi\3
 

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