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What's the best way to work out any percentage of a given number, e.g. 63% of 450?

The best way to approach this is to begin by working out what 1% of 450 would be: 450 is 100% of 450 So to work out what 1% of 450 is: 450 ÷ 100 = 4.5 Now we know that 1% of 450 is 4.5To work out 63% of 450,...
IW
Answered by Isobel W. • Maths tutor
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What are the first 4 non-zero terms in the binomial expansion of (2+3x)^6

Well in a binomial expansion we need to remember the formula (1+x)^n = 1 + nx + (n(n-1)(x^2))/2! + (n(n-1)(n-2)x^3)/3! + ... (I can draw this out properly on the whiteboard app)There is another formula but t...
KG
Answered by Kester G. • Maths tutor
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Simplify √(4x^8).

√(4x 8 ) = √4 x √(x 8 ) = 2 x (x 8 ) 1/2 = 2x 4 Remember that (x n ) p = x np .
DS
Answered by Della S. • Maths tutor
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Differentiate f(x) = (3x + 5)(4x - 7)

A good way to approach this question is to first expand the brackets . This gives 12x 2 - 21x + 20x - 35 (remember to take the negative seven into account). We can then simplify this to give 12x 2 - x - 35 ....
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Answered by Akanksha D. • Maths tutor
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Expand and simplify the following expression: x(5x – 2) – 3(x2 – 2x + 7)

5x2 – 2x – 3x2 + 6x – 21= 2x2 + 4x − 21
Answered by • Maths tutor
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