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Given that 2cos(x+50)°=sin(x+40)° show tan x° = tan 40°/3

The formulae for the sum the sine and cosine of two angles are: 2(cos x°cos 50°- sin x°sin 50°)= sin x°cos 40°+cos x°sin 40°cos 50°= sin 40°sin 50° = cos 40° Therefore, 2 cos x°sin 40°- 2 sin x°cos 40° = ...

PT
Answered by Prashasti T. Maths tutor
7706 Views

Integrate x * sin(x) with respect to x by using integration by parts

The general formula for integration by parts to integrate something of the form u * v' is: u * v - (integral)[ (u' * v) dx ]. Thus we first need to write x * sin(...

JW
Answered by Jamie W. Maths tutor
5235 Views

write 2(sin^2(x)- cos^2(x)) + 6 sin(x) cos(x) in terms of cos(2x) and sin(2x)

We use the following double angle formulae cos(2x) = cos^2(x) - sin^2 (x) and sin(2x) = 2sin(x)cos(x) to see that 2(sin^2(x)- cos^2(x)) + 6 sin(x) cos(x) = -2-(sin^2(x)+ cos^2(x)) + 3*2 sin(x) cos(x) = -2...

NR
Answered by Nicola R. Maths tutor
5393 Views

Factorise and solve x^2 -4x -12=0

x2 - 4x -12 is a quadratic equation with a general formula. It can be factorised by into brackets and solved.By looking at the equation, the last term is negative so one number in the factorise...

MM
Answered by Mitchel M. Maths tutor
8557 Views

How does proof by induction work?

When using proof by induction we most often prove a statement P for positive integers n. We think about the problem in a domino-toppling fashion. The first step is to write out P(n=1), so inserting 1 for ...

AC
Answered by Ana C. Maths tutor
1513 Views

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