Qualification > Math

C3 Trigonometry help!

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IO4567:
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 ? 360º, which satisfy the equation

2sinx = cos(x - 60)

Thank you!

astarmathsandphysics:
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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