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How should I prepare myself for my GCSE/A Level Oral Exam?

The best long-term advice I can give is that you have got to practice speaking the language as much as possible. Try to organise weekly sessions with teachers/language assistants/online tutors to get used...

Answered by Simon C. • Spanish tutor

6894 Views

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

41185 Views

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

34548 Views

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

81823 Views

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

4001 Views