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Find R and a such that 7*cos(x)+3*sin(x)=Rcos(x-a)

Use the cosine trig identity, cos(a-b)=cos(a)cos(b)+sin(a)sin(b) ,to write Rcos(x-a) as R(cos(x)cos(a)+sin(x)sin(a)).Now we can equate the coefficients of the sines and cosins on either side of the equation ...
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Answered by Darius Y. • Maths tutor
7107 Views

why is the number e important?

When we work with circles, one of the most popular things to pop up is pi. We know that for any circle the circumference divided by the radius gives pi, without failure always. Pi is a number that’s been fou...
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Answered by Sam V. • Maths tutor
3281 Views

How to answer a difficult interview question or one you don’t know the answer to?

Breathe.Try not to panic. While it may seem unfamiliar, Oxbridge interviewers aren’t looking to trick you in any way, and instead want to see how you apply what you know to new situations. There’s no pressur...
PS
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What is an optical isomer?

Optical isomers are a form of stereoisomers which are chemical species with the same structural formula, but have a different arrangement of atoms in 3-dimensional space. Optical isomers are characterised by...
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Answered by Thomas D. • Chemistry tutor
2704 Views

How do you write a thoroughly coherent essay?

A logical and comprehensible structure is essential to every essay if it is to be coherent enough to hit the top bands. Highlighting the key words in the chosen/given question and thoroughly ordering your ar...
RS
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