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Find dy/dx of y = a^x

To differentiate a function of the form y=a^x you need to use a neat little trick to rewrite a^x in the form of something you already know how to differentiate. Using the fact that e^ln(x) is equal to x, y =...
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Answered by Tutor33284 D. • Maths tutor
24924 Views

Show how '2sin(x)+sec(x+ π/6)=0' can be expressed as √3sin(x)cos(x)+cos^2(x)=0.

To do this question we must first be aware of a few trigonometric identities. 1. sec(x) = 1/cos(x). 2. cos(A + B) = cos(A)cos(B) - sin(A)sin(B). (double angle formula) 3 . sin^2(x) = 1 - cos^2(x) Before divi...
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Answered by Ruadhan P. • Maths tutor
10662 Views

What is Coulomb's law

These are usually 2 or 3 mark questions and should be a really easy source of marks in any paper. The marks will be awarded for stating the 2 key point of the law and in some cases for writing out the equati...
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Answered by Ruadhan P. • Physics tutor
22212 Views

How do you find the integral of 'x sin(2x) dx'?

To begin, notice that the expression involves 2 functions of x multiplied together, this means we can approach the problem using integration by parts. Integration by parts can be expressed as '∫ u (dv/dx) dx...
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Answered by Ruadhan P. • Maths tutor
23851 Views

How can I reach the top grade band in my writing section?

I would say there are three key ways to achieve this. Firstly, it is hugely important to use an advanced conditional phrase which involves the imperfect subjunctive. For example, if you were writing about th...
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Answered by Edward W. • Spanish tutor
3500 Views