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Express cos5x in terms of increasing powers of cosx

De Moivre's theorem: (cos5x + isin5x) = (cosx + isinx)⁵ To get cos5x we will need to expand (cosx + isinx)⁵ and then take the real parts. Binomial expansion: (cosx + isinx)⁵

Answered by Chris S. • Further Mathematics tutor

31902 Views

Integrate cos(2x)

The intergral for cosx is sinx, but '2x' must be considered.

When differentiating a sinx/cosx function, the '2x' would be differentiated separately

and placed in the front (multipling). So w...

Answered by Gold O. • Maths tutor

17980 Views

The area of a rectangle is 8cm^2. The rectangle is (3x+1) by (2x+5). Find the value of x

Area of a rectangle is width times height (3x+1)(2x+5)= 6x²+15x+2x+5 6x²+17x+5 Set formula of area equal to known area value. 6x²+17x+5= 8 6x²+17x-3 ...

Answered by Conrad D. • Maths tutor

5943 Views

How should you structure paragraphs in your essay?

A strong introductory paragraph is crucial but it does not need to be too long, save your words for the middle section. As well as this, a strong concluding paragraph that links all your points together i...

Answered by Jessica V. • English Literature tutor

3555 Views

What is the best way to approach analysing a historical source?

Firstly it is important to cover the who, what, when and where of the source to gain a better understanding. Next, the content of the source should be picked apart to find the true point of it. This shoul...

Answered by Jessica V. • History tutor

2153 Views