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Express cos(4x) in terms of powers of cos(x)

By quoting De Moivre's theorem, (r(cos(x) + isin(x)))ⁿ = rⁿ(cos(nx) + isin(nx)), we can realise that cos(4x) is a result of the real parts of (cos(x) + isin(x))⁴

Answered by Luis D. • Further Mathematics tutor

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Why is phenylamine a weaker organic base than ethylamine?

Phenylamine contains a phenyl group attached to the amine. Phenyl groups have a delocalised system of electrons as a result of p orbitals from the 6 adjacent carbon atoms overlapping and "merging&quo...

Answered by Adam W. • Chemistry tutor

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How do you go about differentiating a^x functions?

A key point to remember here is that a^x could mean the base (a) is not “e”-that special number which has a gradient function, dy/dx (the differential), EQUAL to the function itself, y=e^x. When "a&q...

Answered by Adam W. • Maths tutor

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In terms of reaction mechanisms, what exactly is the rate-determining step?

The easiest way to visualise this is to imagine a line of four dinner ladies serving you different parts of a school meal e.g. the first peas, the second mash potatoes, the third chicken and the fourth gr...

Answered by Adam W. • Chemistry tutor

4152 Views

To what extent do the structures and functions of DNA and RNA differ?

Firstly, there are chemical differences between the two nucleic acids. DNA has the following structural properties:-double stranded and anti-parallel polymer held together by (relatively) weak hydrogen bo...

Answered by Adam W. • Biology tutor

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