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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 repr...

Answered by Edward H. • Maths tutor

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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 an...

Answered by Molly B. • Maths tutor

8319 Views

Derive double angle formulas from addition formulae

sin2x = 2sinxcosxcos2x = cos²x - sin²x=2 cos²x - 1= 1 - 2sin²xtan2x = (2tanx)/(1-tan²x)

Answered by Alexander H. • Maths tutor

3609 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 curv...

Answered by Kelvin L. • Maths tutor

3774 Views