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Write cosx - 3sinx in the form Rcos(x + a)

Rcos(x + a) = Rcosxcosa - Rsinxsina
By comparing cosx - 3sinx to the new expression, we can see that:
Rsina = 3 and Rcosa = 1
If we square both and add them, we can see R = √(1²

Answered by Odin G. • Maths tutor

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Samuel had 3 piles of coins, I, II and III. Altogether there was 72p. Pile II had twice as much as pile I. Pile III had three times as much as pile II. How much money was in Pile III?

First let coins in pile I equal x. Then we the question tells us II has twice pile A so we can now write this as 2x. Finally, we can write pile III as 6x - reason is that III has three times pile II...

Answered by Syed R. • Maths tutor

3165 Views

What is Ionisation Energy and the three factors that affect it? 2)State and explain the general trend in first ionisation energies for the Period 3 elements.

Ionisation energy is the energy required to remove 1 mole of electrons from each atom in 1 mole of gaseous atoms to form 1 mole of gaseous ions.For...

Answered by Kadambari R. • Chemistry tutor

16003 Views

How do I explain what effect an increase in government spending may have on unemployment and inflation in an economy?

The best way to answer this question would be by using the help of a Keyenesian diagram. After drawing the standard long-run supply curve and aggregate demand curves we can show what effect an increase in...

Answered by Abid R. • Economics tutor

2675 Views

With reference to the score, discuss Debussy's 'The Little Shepherd' from 'Children's Corner' L.113 with particular emphasis on the use of texture

Debussy's 'The Little Shepherd' is a short piano miniature which juxtaposes moments of graceful, soloistic monophony with harmonically colourful passages of melody-dominated homophony. The key of this mus...

Answered by Callum S. • Music tutor

4343 Views