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Cube roots of 8?

8 traditionally has 1 cube root. 2. This is only the real root. It has 2 more complex roots!How can we see this?Consider a vector on the argand diagram. If we square it. What happens to it's magnitude and ar...
VJ
4643 Views

Differentiate: y=x^x

First take log’s each side as it would turn our complicated function into something differentiable by chain rule. ln y = x*ln x Then differentiate y with respect to x: d(ln y)/dx = ln x + 1 1/y * dy/dx = ln ...
MV
2986 Views

Use induction to prove that for all positive integers n, f(n)=2^(3n+1)+3x5^(2n+1) is divisible by 17.

Prove the basis to be true. Let n=1 and this gives f(1)=16+375=391 which is divisible by 17. Now assume that if we let n=k f(k) is divisible by 17. If we now let n=k+1 and prove f(k+1) is divisible by 17 we ...
MH
3531 Views

Give the general solution of the second order ODE dy2/d2x - 4dy/dx + 3 = 0

Solving the ansatz equation x^2 - 4x + 3 = gives 2 equal roots where x = 3 and x = 1The general solution therefore is y = Ae^3x + Be^x where A and B are arbitrary constants
MN
3398 Views

What IS a Taylor Series?

If you have studied Physics, you may be familiar with the small angle approximation cos θ ≈ 1 - θ 2 / 2. This is a surprisingly accurate approximation for small values of theta (try it!), but where does it c...
DM
3177 Views