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James wins the lottery and gets £200,000. He decides to spend 10% of his winnings and invest the rest. From the money he has invested, he receives interest of 3% per year. How much money does James have after 5 years (to the nearest pound)?

James starts with £200,000. He then spends 10% of his winnings: 200,000*(1-0.1)=180,000 The 1 represents 100%, which the amount of money James starts with. He then spends 10%, which is represented by the -0....
EH
Answered by Edward H. • Maths tutor
3797 Views

How do I know when to use the cosine or sine rule?

Both the cosine and sine rule are used to find either a missing side length or angle of a triangle that doesn't have a right angle. The cosine rule is used when you know the length of two sides and the angle...
MB
Answered by Molly B. • Maths tutor
10363 Views

Derive double angle formulas from addition formulae

sin2x = 2sinxcosxcos2x = cos 2 x - sin 2 x=2 cos 2 x - 1= 1 - 2sin 2 xtan2x = (2tanx)/(1-tan 2 x)
AH
Answered by Alexander H. • Maths tutor
4147 Views

Find the equation of the normal to the curve x^3 + 2(x^2)y = y^3 + 15 at the point (2, 1)

The first thing when seeing such a question is to find out what the question wants you to do and plan your method to do so.In this case, the question asks you to find the normal of a curve at a given point (...
KL
Answered by Kelvin L. • Maths tutor
4401 Views

Expand (x-3)(x+7)

FOIL Method: F - First x x = x 2 O - Outside x 7=7x I - Inside -3 x=-3x L - Last -3 7= -21 Add all the results up to get the answer: x 2 +7x-3x-21 = x 2 +4x-21
ML
Answered by Martin L. • Maths tutor
8648 Views