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Find a and b (both real) when (a+b*i)^2=i.

Every complex number has a real and imaginary part. For the complex number z=a+bi the notation for real and imaginary parts respectively are Re(z)=a and Im(z)=b . If you know this, many complex algebra equat...
UA
Answered by Urte A. • Maths tutor
1955 Views

Find the derivative of the next function using the implicit method: x^2 sin(x+y)-5 y e^x​​​​​​​=0

Using the implicit form derivative rule: y'=-F x ' / F y ' : y'=-(2 x sin(x+y)+x 2 cos(x+y)-5 y e x ) / (x 2 cos(x+y)-5 e x )
LA
Answered by Lucia A. • Maths tutor
2000 Views

How do radians work? Why can't we just keep working with degrees in school?

Degrees are a made up unit; mathematicians simply decided that a complete revolution of a circle has 360 degrees, without that number actually meaning anything. Tecnically any number could have been picked t...
HD
Answered by Hans D. • Maths tutor
2402 Views

Determine the coefficient of y^3 in the binomial expansion (2x-3y)^4

Using the method of binomial expansion (which I will cover in more detail) we get (2x-3y)^4 = + 1(2x)^4(3y)^0 - 4(2x)^3(3y)^1 + 6(2x)^2(3y)^2 - 4(2x)^1(3y)^3 + 1(2x)^0(3y)^4 = = 16x^4 - 96x^3 y + 216x^2 y^2 ...
DM
Answered by Davids M. • Maths tutor
11950 Views

Let f (x) = sin(x-1) , 0 ≤ x ≤ 2 π + 1 , Find the volume of the solid formed when the region bounded by y =ƒ( x) , and the lines x = 0 , y = 0 and y = 1 is rotated by 2π about the y-axis.

Draw a rough sketch of the graph of f(x) = sin(x-1) to get an idea of what the region looks like. Realise that the normal volume of revolution for the area between x axis and the f(x) is given by V = pi* int...
AS
Answered by Ankur S. • Maths tutor
7506 Views