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How do I expand a factorised expression?

Take example (x+3)(x-4) We use FOIL - first, outer, inner, last We multiply each part by the other part. First -> x times x = x 2 . Outer -> x times -4 = -4x (remember the minus infront of the 4), Inne...
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Answered by Sarah K. • Maths tutor
3796 Views

I can differentiate exponentials (e^x), but how can I differentiate ln(x)?

[Differentiate y = ln(x)] This is an example of many situations in maths where you need to solve something that is similar to what you can solve, but not in its current form. A good idea, then, is to see wha...
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Answered by Adam L. • Maths tutor
3588 Views

Express f(x) = x^2 + 5x + 9 in the form (x + a)^2 + b, stating the values of a and b.

The question asks you to complete the square on the function f(x). First, we split the function: f(x) = (x^2 + 5x) + 9 And recognise that we need the form (x^2 + 2k + k^2). Identifying 2k = 5, we have that k...
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Answered by Lee B. • Maths tutor
7948 Views

Simplify (4^2)*(2^3)*16

Indice rules are fundamental in answering this question 1) (a b )(a c ) = a (b+c) 2) (a b )/(a c ) = a (b-c) 3) (a b ) c = a (b c) 4) a (-b) = 1/(a b ) 5) a 0 = 1 We can simplify 4 2 to (2 2 ) 2 and using ru...
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Answered by Oak W. • Maths tutor
3864 Views

Solve 6x-5 > 4x+13

6x - 5 > 4x + 13 (Take away 4x from each side) 2x - 5 > 13 (Add 5 to each side) 2x > 18 (Divide both sides by 2) x > 9
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Answered by Namita H. • Maths tutor
7182 Views