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How do I evaluate composite functions?

Suppose you have 2 functions: f(x) = 3x 2 , g(x) = log 3 (x). These are arbitrary, any functions would work. Evaluate f(g(x)): let y = log 3 (x) ( = g(x) ), then f(g(x)) = f(y) = 3y 2 = 3[log 3 (x)] 2 . The ...
SG
Answered by Seb G. • Maths tutor
5046 Views

How do I differentiate implicitly?

The most important thing to remember when differentiating implicitly is that y is a function of x. Rewriting y as y(x) often makes it much clearer. For example, evaluate d/dx (y 2 ): using the aforementioned...
SG
Answered by Seb G. • Maths tutor
5332 Views

A cup of coffee is cooling down in a room following the equation x = 15 + 70e^(-t/40). Find the rate at which the temperature is decreasing when the coffee cools to 60°C.

First, we need to find the value of t when x = 6p°C. We are told that after t minutes the temperature, x, will be 60°C; so we can insert 60 into the equation for x: 60 = 15 + 70e^(-t/40) Secondly, we can rea...
NA
Answered by Nathan A. • Maths tutor
12569 Views

What are the events in the cardiac cycle?

The cardiac cycle is the series of events that leads to blood being pumped to the lungs and around the body. The cycle begins with the SAN (sino-atrial node). This is the hearts 'pacemaker'. It sends out a n...
TC
Answered by Thomas C. • Biology tutor
9336 Views

Find the value of 2∫1 (6x+1) / (6x2-7x+2) dx, expressing your answer in the form mln(2) + nln(3), where m and n are integers.

This fraction can’t be integrated easily, but if we split it using partial fractions, these will be easier to integrate. To do this, we need to factoise the denominator, as this will follow the method of par...
JM
Answered by Jed M. • Maths tutor
14383 Views