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How to determine the number of unique real roots of a quadratic equation.

Take any quadratic equation, eg/ 3x 2 +4x-2=5 , and rearrange to equal 0 , ie/ 3x 2 +4x-7=0 (if you have an expression, ie/ there is no equals sign, then simply equate the expression to 0 ). Now, we use the ...
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Answered by Yaniv P. • Maths tutor
23551 Views

Describe how blood vessels are able to assist in the control of body temperature.

If body temperature is too high: Capillaries dilate, increasing the blood supply to the skin and allowing heat to be lost from the body by radiation. If body temperature is too low: Capillaries constrict, re...
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Answered by Merrin W. • Biology tutor
4779 Views

How do I do a proof by induction?

For this explanation we will use the following example from a 2013 exam paper: If u 1 = 2 and u n+1 =(5u n -3)/(3u n -1), then prove that u n =(3n+1)/(3n-1) for all n>=1 The first step of any proof by ind...
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5380 Views

How do I find the integral ∫(ln(x))^2dx ?

This problem is all about using integration by parts, so let's start by quoting the formula for integration by parts: ∫u*(dv/dx)dx = uv - ∫v*(du/dx)dx To get the integral we want on the left hand side we can...
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Answered by Samuel C. • Maths tutor
12614 Views

What is the force on a moving charged particle in a magnetic field, and why is no work done by this force when it accelerates the particle?

A particle with electric charge q , mass m and velocity v in a constant magnetic field B experiences a force due to the field: F = q v X B The ' X ' ( cross-product ) means that the force is always at 90° ( ...
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Answered by Rich P. • Physics tutor
13657 Views