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IGCSE/GCSE/O & A Level/IB/University Student Forum
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C3 Trigonometry help!
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Topic: C3 Trigonometry help! (Read 705 times)
IO4567
Newbie
Posts: 23
Reputation: 15
C3 Trigonometry help!
«
on:
February 10, 2010, 03:54:44 pm »
Please could someone help me with this question... I've been at it for ages
Find, to 1 decimal place, the values of
x
, 0?
x
? 360ยบ, which satisfy the equation
2sin
x
= cos(
x
- 60)
Thank you!
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astarmathsandphysics
SF Overlord
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Free the exam papers!
Re: C3 Trigonometry help!
«
Reply #1 on:
February 10, 2010, 07:03:26 pm »
2sinx = cos(x - 60)
2sinx=cosxcos60+sinxsin60
2sinx=1/2cosx+sqrt(3)/2 sinx
group the sinx terms
sinx(2-sqrt(3) /2)=1/2cosx
divide by cosx to get tanx=(1/2)/(2-sqrt(3) /2) so x=23.8 degress and 180+23.9=203.9
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IGCSE/GCSE/O & A Level/IB/University Student Forum
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Math
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C3 Trigonometry help!