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Evaluate:
7pi 11pi
sin^2 ---- + cos^2 -----
6 6
7pi = 21.99114858 divided by 6 > 3.665191429
11pi = 34.55751919 divided by 6 > 5.759586532
sin^2 3.665191429 > isssssssss
cos^2 5.759586532 > isssssssss
HELP
do u have to do
sin 3.665191429 ^ 2 like this?
Last edited by unique (2006-11-01 10:17:05)
Desi
Raat Key Rani !
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So, you first take the sin, and then square the result:
But are you supposed to get an exact value for this ? Or is a decimal ok?
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if i do that
than my answer comes out to
4.086538401 x10 -03
on the calculator
Desi
Raat Key Rani !
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That happens because your calculator is in Degree Mode. You need it in Radian mode, because angles like 7pi/6 are in Radians.
Last edited by polylog (2006-11-01 10:57:16)
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oh yeah thanks
i had my calculaor on complx instead of comp
Desi
Raat Key Rani !
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so answer is the total is
1.068934976
so final answer is 1.07
Desi
Raat Key Rani !
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Did you round off a lot of the numbers in between steps? I get the answer as 1 exactly...
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Oh, of course! cos(11π/6) = cos(7π/6).
Substituting that in gets you sin²(7π/6) + cos²(7π/6), which is 1 because sin² + cos² always is.
It's so simple to work out now we know the answer.
Why did the vector cross the road?
It wanted to be normal.
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