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When do I use a cosine rule over a sine rule?

Both the sine and the consine rule applies to any triangle, you do not necessary need a right angle! You can usually use the cosine rule when you are given two sides and the included angle (SAS) or when you ...
JF
Answered by Jessica F. Maths tutor
128872 Views

How do you integrate xcos(x)?

Using integration by parts: split xcos(x) into x multiplied by cos(x). Differentiating x gives 1 and integrating cos(x) gives sin(x). The integral of xcos(x) can therefore be rewritten as xsin(x) - integral ...
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Answered by Aleksandr B. Maths tutor
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How to integrate lnx by parts?

Integration by parts formula: ∫ u dv/dx = uv - ∫ du/dx v dx To solve this problem we need to use a trick by thinking of lnx as lnx 1 So we can choose: u=lnx, dv/dx=1 The next step is to find du/dx and v. du/...
RJ
Answered by Ryan J. Maths tutor
9724 Views

How do you find the inverse of a function?

So you are asked to find the inverse of a function f(x). The inverse function is denoted by f -1 (x). To help with this we can use the identity f(f -1 (x))=x. Now, we need to define y=f -1 (x). Example: f(x)...
RJ
Answered by Ryan J. Maths tutor
7378 Views

What are the differences between arithmetic and geometric sequences?

An arithmetic sequence has a constant difference between each term. For example: 2,4,6,8,10,12,… We can see clearly that all the terms differ by +2. We call this the common difference, d. A geometric sequenc...
RJ
Answered by Ryan J. Maths tutor
168264 Views