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How can you find out if two lines expressed in their vector form intersect?

Let the lines be: r 1 = (a, b, c) + t(d, e, f) r 2 = (g, h, i) + s(j, k, l) Since t and s above are variables and the rest of the letters are constants, the only way to change the point which the vector equa...
YI
Answered by Yordan I. Maths tutor
4678 Views

Why is Pythagoras theorem (a^2 + b^2 = c^2) true for every right angle triangle?

Firstly let's take a right angle triangle. Label its sides a,b, c for the hypotenuse. Then arrange 4 of these triangles into a large square, with a smaller square contained within it. The area of the smaller...
EG
Answered by Edwyn G. Maths tutor
8179 Views

How to Integrate ln(x)?

Integrating this expression is a simple trick. We use integration by parts. For this we need a function we can integrate and a function we can differentiate. We know how to differentiate ln(x) which is 1/x. ...
JR
Answered by Jordan R. Maths tutor
7580 Views

Prove the trigonometric identity tan^2(x)+1=sec^2(x)

We can start with the identity sin 2 (x)+cos 2 (x)=1 If we divide through the equation by cos 2 (x), we get: sin 2 (x)/cos 2 (x) + cos 2 (x)/cos 2 (x) = 1/cos 2 (x) If we look at the left hand side of the eq...
CW
Answered by Charlotte W. Maths tutor
25192 Views

Find the equation of the tangent to the curve y = 2x^2 + x - 1 at the point where x = 1.

To get the required tangent equation we need its gradient and the coordinates of a point it passes through. We can then substitute it into the formula y - y 1 = m(x - x 1 ). 1. Finding the gradient: To find ...
BT
Answered by Beth T. Maths tutor
12367 Views