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Question
1. Solve the equation in the interval -720degree < theta < 0degree.
2. If sin(x+30degree)=1/2sinx, prove that tanx=1 over 1-square root of 3.
Hi Xaba,
1) What equation???
2) sin(x + 30) = sinx.cos30 + sin30.cosx
= (√3/2)sinx + (1/2)cosx
If sin(x + 30) = (1/2)sinx, then
(√3/2)sinx + (1/2)cosx = (1/2)sinx
(√3/2)sinx - (1/2)sinx = -(1/2)cosx
multiplying through by 2
(√3)sinx - sinx = -cosx
(√3 - 1)sinx = -cosx
sinx/cosx = -1/(√3 - 1)
tanx = 1/(1 - √3)
Regards
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| Comment | The problem on trigonometry was resolved within hours, which made it possible for me to understand much better on how to solve a complex questions. Thanks Ahmed Salami | ||
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Ahmed Salami
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I can provide good answers to questions dealing in almost all of mathematics especially from A`Level downwards. I can as well help a good deal in Physics with most emphasis directed towards mechanics.
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An engineering graduate. I have been doing maths and physics all my life.
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