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Using the equation cos(a+b) = cos(a)cos(b) - sin(a)sin(b) or otherwise, show that cos(2x) = 2cos^2(x) - 1.

First let a = b = x such that: cos(a + b) = cos(a)cos(b) - sin(a)sin(b) becomes: cos(x + x) = cos(x)cos(x) - sin(x)sin(x) Leading to: cos(2x) = cos 2 (x) - sin 2 (x) Using the fact that sin 2 (y) + cos 2 (y)...
BH
Answered by Benjamin H. • Maths tutor
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Give the definition simple harmonic motion and write down the defining equation for such motion stating the meaning of any symbols involved.

Simple harmonic motion is defined as a form of periodic motion in which a point or body oscillates in such a way that the acceleration of the point or body is directly proportional to its displacement from t...
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Answered by Benjamin H. • Physics tutor
29935 Views

Explore the ways in which Yeats presents his journey in ‘Sailing to Byzantium’

Yeats wrote of Byzantium, “I symbolise the search for the spiritual life by a journey to that city”[1], and indeed, his poem reflects this quest for some form of religion. From a foundation in Christianity, ...
HK
8287 Views

What is the best way to plan an essay?

When answering an essay question, the most important stage, in my view, is the planning. Personally, I like to make a mind map, but it really depends on what you feel the most comfortable with, and I recomme...
EO
Answered by Emma O. • History tutor
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Why is the argument of a+bi equal to arctan(b/a)?

Think about the point a+bi on the complex plane. Specifically, a is how far along the x (real) axis, and b is how far up the y (imaginary) axis the point is. If you draw a line connecting the origin and the ...
MS
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