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Given the ratio of x : y is 7 : 4 and x + y = 88. Work out the value of x – y

7x = 4yx=4y/7If we insert this into our other equation.4y/7 + y = 8811y/7 =88y = 56As we knowx =4y/7X= 4*56/7 = 32Then we can work out the answer X - Y = 32 - 56 = -24
SK
Answered by Salih K. • Maths tutor
4929 Views

If f(x)=(x^3−2x)^5 , find f'(x).

f(x)=(x 3 -2x) 5 If we look at this function, we can see that it can be split into two functions, one hiding in the other one. Because of that, to solve this problem we will need the Chain rule: f(g(x))' = f...
RS
Answered by Radovan S. • Maths tutor
6098 Views

What is the indefinite integral of xlog(x)?

The integral can be split into two different functions of x which is a hint that we must use the integration by parts method. The method is defined as ∫ uv’ dx = uv - ∫ u’v dx . If we let u = log(x) and v’ =...
WH
Answered by William H. • Maths tutor
5071 Views

Solve the following simultaneous equations: x^2 + y^2 = 29 and y - x =3

This question is slightly trickier than normal simultaneous equations, because we have values to the power of 2. What we can do is make either y or x the subject of the 2nd equation (y-x = 3). For this examp...
TD
Answered by Trushna D. • Maths tutor
4109 Views

Using the binomial theorem, find the coefficient of x^4*y^5 in (x-2y)^9.

The term containing x 4 y 5 will be C(9, 5) x 4 (-2y) 5 = (9!/(5!4!)) x 4 (-2) 5 y 5 The coefficient of which will be 126 -32= -4032
GH
Answered by George H. • Maths tutor
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