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How do I rationalise the denominator of √2+1]/√2-1?

We must choose something to multiply the numerator and denominator of the fraction by the same thing, and the best thing to choose is the difference of two squares (since (x^2-y)(x^2+y)=x^2-y^2 ). So we do (...
HJ
Answered by Harry J. • Maths tutor
6219 Views

Outline the difference between "positive" and "negative" freedom?

The distinction between positive and negative notions of freedom can be traced to Isaiah Berlin and his 1936 essay: "Two Concepts of Liberty". Negative freedom is defined as freedom from obstacles,...
RS
Answered by Rooban S. • Politics tutor
18568 Views

What is an immobilised enzyme and what are the advantages of their use?

Immobilised enzymes are enzymes that have been trapped into an inert matrix or material (such as calcium alginate) which prevents them from moving during the reaction process. Whole cells such as yeast and b...
RS
Answered by Rooban S. • Biology tutor
42918 Views

Why is there more than one solution to x^2 = 4?

Think about it as 'What numbers can be x to get 4'. Remember that when you square a number the answer is always positive? Here is a situation in which it's important to consider both of the possible solution...
BT
Answered by Benjamin T. • Maths tutor
4089 Views

Kinetic theory describes the movement of particles in three states of matter. If a cube of ice is put in a tin with a tight fitting lid and continuously heated, why does the lid explode off?

Before heating: Ice and air present in the tin, the ice particles vibrate about fixed positions, they do not exert a pressure on the lid at this time, air particles inside the tin hit the lid but exert the s...
TM
Answered by Tom M. • Physics tutor
3807 Views