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What is Le Chatelier's Principle?

By defintion, Le chatelier's principle states that if a reaction at equilibrium (i.e a reversible reaction) is subject to a change in concentration, pressure or temperature the system will act in a way to co...
RC
Answered by Rebecca C. Chemistry tutor
5377 Views

Describe the difference between a covalent bond and an ionic bond.

An ionic bond if formed from the transfer of electrons from the outer shell of atoms. The donor of the electrons becomes positively charged as it has more protons than electrons, and so is called a cation. T...
HT
10410 Views

How to I factorise a quadratic equation?

I think the best way to show how to do this is with an example "Factorise 6x 2 + 7x - 3" Looking at that expression, we can't factorise it straight away, so we'll have to rewrite it in a way that a...
DB
Answered by Daisy B. Maths tutor
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Express Cosx-3Sinx in form Rcos(x+a) and show that cosx-3sinx=4 has no solution MEI OCR June 2016 C4

Cosx-3sinx =R(CosxCosa-SinxSina) 1=Rcosa R^2=1^2+3^2 r=(10)^0.5=(approx)3.16 a=1.249 3.16Cos(x+1.249)=4 has no solution as 4<3.16 so as cos(theta) has maximum value of 1, there are no solutions
JP
Answered by Jakub P. Maths tutor
5650 Views

How do you find the area of a semi circle with a radius of 7cm?

You should remember that a semi circle is the same as half a circle, therefore the area must be half as well! The formula for the area of a circle is pi r^2. If we use this, the area of our circle = pi x (7^...
CJ
Answered by Cindiya J. Maths tutor
13558 Views