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Find the stationary points on the curve y = x^3 + 3x^2 - 9x - 4

A stationary point is where the gradient is exactly zero - the curve is neither increasing or decreasing. This means that we need to differentiate y to find dy/dx and then set this equal to 0. Doing this, us...
RR
Answered by Richard R. • Maths tutor
17406 Views

Calculate the standard enthalpy of combustion of a methane sample by using the standard enthalpies of formation.

Write the equation and balance it. CH4 + 2O2 --> CO2 + 2H2O Assign the enthalpies of formation and the sign of the energy value with the corresponding molecule (Will demonstrate my technique if needed). e...
AC
Answered by Axel C. • Chemistry tutor
29577 Views

By writing tan x as sin x cos x , use the quotient rule to show that d dx ðtan xÞ ¼ sec2 x .

First write tanx as sinx/cosx as it is always helpful to use what additional information the question gives you. It says we must use the quotient rule to calculate the result so it is also a good idea to wri...
DB
Answered by Daniel B. • Maths tutor
7873 Views

State Faraday's law of electromagnetic induction

The induced e.m.f. is equal to the rate of change of magnetic flux linkage. Can use equation with all terms defined.
DO
Answered by Daniel O. • Physics tutor
5929 Views

Find the integral on ln(x).

Integrate by parts, identifying that dv/dx = 1, u = ln(x) and therefore v = x and du/dx = 1/x. Sub into the parts equation to find the answer to be xln(x) - x + c.
DO
Answered by Daniel O. • Maths tutor
4112 Views