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If f(x)=7xe^x, find f'(x)

f(x) = 7xe x Using the product rule: [f'(x)=u*(dv/dx)+ v*(du/dx)]Let u=7x and v=e x Therefore, du/dx=7 and dv/dx=e x Hence, f'(x) = 7xe x + 7e x
LM
Answered by Lanya M. • Maths tutor
4981 Views

How to express (4x)/(x^2-9)-2/(x+3)as a single fraction in its simplest form.

First we should be aware of the relationship bewteen the denominator of the two fractions. Since x^2-9=(x+3)(x-3), we can multiply (x-3) on both numerator and denominator of the fraction of 2/(x+3). Hence th...
KY
Answered by Kexin Y. • Maths tutor
4890 Views

Use logarithms to solve the equation 2^(n-3) = 18000, giving your answer correct to 3 significant figures.

To find the answer first you have to take a log of both sides. I am going to use log to the base 2 for my example - but any base will work as long as they are the same on both sides of the equals sign log(2 ...
EJ
Answered by Emily J. • Maths tutor
7325 Views

A block of mass 5kg is at rest on a smooth horizontal table, and connected to blocks of 3kg and 4kg which are hanging by strings via pulleys on either end of the table. Find the acceleration of the system and the tension in each string.

[would draw diagram to make easier]. We can use Newton's Second Law (F=ma) to resolve the forces acting on each of the blocks (label string on 3kg side T 1 and on 4kg side T 2 , and looking at the diagram us...
DO
Answered by Daniel O. • Maths tutor
4411 Views

What is a hypothesis test

A hypothesis test is used for deciding if something is statistically significant or not. You begin stating your two hypotheses H0: Null hypothesisH1: Alternative hypothesisFor example in a linear regression,...
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Answered by David A. • Maths tutor
3999 Views