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Find the derivative of sin^2(x)

Using the chain rule we differentiate the ‘outside function’, then differentiate the ‘inside function’ and multiply both derivatives together giving 2sin(x)cos(x)
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Answered by David R. • Maths tutor
5384 Views

How do I know which out of the Sine and Cosine rule I should use?

If you look at the formulae for the Sine and Cosine rules you'll see that the Sine rule involves two angles and two sides and the Cosine rule involves one angle and three sides.So have a look at the problem ...
JH
Answered by Julian H. • Maths tutor
5775 Views

Find an expression in terms of powers of cos(x) for cos(5x)

De Moivre's theorem states that e ix = cos(x) + isin(x) or that e i5x = cos(5x)+ isin(5x). If the real components of both sides of this equation is taken we can see that : cos(5x) = Re[e i5x ] where Re means...
AA
Answered by Arnav A. • Maths tutor
7949 Views

Differentiate f(x)=(x+sin(2x))^4

This is an actual question from an EdExcel C3 paper worth 4 marks. Ok so first thing we do is look at the function and try and determine which of our 3 differentiation rules we use. Is it a Product / Quotien...
UB
Answered by Udayan B. • Maths tutor
4695 Views

Solve x^2+10x+5=0 using completing the square.

Completing the square is one of the 3 common ways to solve a quadratric equation (other two being factorising and using the quadratic formula).Using completing the square method, you manipulate the first two...
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Answered by Vijendra V. • Maths tutor
4786 Views