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Expand and simplify 3(2x + 5) – 2(x – 4)

Firstly, to expand an equation like this, you must multiply the brackets by the number outside of the brackets. Make sure that you multiply every number inside the bracket by the number directly outside, and...
AK
Answered by Anna K. • Maths tutor
79651 Views

Explain the Chain Rule

The chain rule is used to differentiate composite functions, ie "a function of a function". In this case we have an outer function and an inner function. For example Differentiate f(g(x)). Here f i...
AC
Answered by Alex C. • Maths tutor
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What is the angle between the position vectors a and b, where a = (6i - j + 3k) and b = (-4i + 2j + 10k)?

cos( AOB ) = a.b /(| a | x | b |) a.b = (6i - j + 3k) . (-4i + 2j + 10k) = (6 x -4) + (-1 x 2) + (3 x 10) = -24 + -2 + 30 = 4 (| a |)^2 = 6^2 + (-1)^2 + 3^2 = 36 + 1 + 9 = 46 -> | a | = 46^(1/2) (| b |)^2...
DH
Answered by David H. • Maths tutor
6748 Views

Solve the simultaneous equations 3x + 4y = 17 and 4x + y = 14

Eq1: 3x + 4y = 17 Eq2: 4x + y = 14 Eq2 x 4: 16x + 4y = 56 Subtract Eq1 from this to isolate x: 16x + 4y - 3x - 4y = 56 - 17 Simplify: 13x = 39 Solve for x: x = 3 Substitute x into Eq1: 3(3) + 4y = 17 9 + 4y ...
DH
Answered by David H. • Maths tutor
9213 Views

What is the median, upper quartile and lower quatile. How do we find them?

The easiest way to explain this would be to use an examplar question. For example: Ben is given a sequence of numbers and is told to find the median, lower quartile and upper quartile. 1,4,5,6,8,9,11,12,14,1...
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Answered by Daniella B. • Maths tutor
19510 Views