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Determine the first derivative of the following curve defined by parametric equations x = 20-5t and y = t^5.

First remember that a parametric curve z = (x(t), y(t)) can be differentiated using the following formula (derived using the chain rule): dz/dt = (dy/dt)/(dx/dt). We should now find dy/dt and dx/dt (which...

Answered by Federico C. • Maths tutor

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When should I use the subjunctive?

The subjunctive is used to express desires, wishes, uncertainties, possibilities and doubts. For example, in Spanish when you wish to say 'I don't think it is sunny', you would use the subjunctive (No cre...

Answered by Matilda O. • Spanish tutor

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Explain how the Kekulé model of benzene is contradicted by the hydrogenation enthalpies of ethene and benzene

The Kekulé model of benzene consists of a 6 membered ring with 3 double bonds. This would imply a hydrogenation enthalpy very similar to that of ethene, since double bonds react with hydrogen in a similar...

Answered by Lukas M. • Chemistry tutor

1578 Views

I don't fully understand the purpose of integration. Could you please explain it to me?

I have written "… " where I would imagine the student is replying. I have then provided prompts assuming that the student did not come up with the answer straight away. Integration can ...

Answered by Rebecca L. • Maths tutor

2577 Views

An ideal gas within a closed system undergoes an isothermal expansion from an initial volume of 1m^3 to 2m^3. Given that the initial pressure of the gas is 10^5 Pa, find the final pressure of the gas following the expansion.

The key word to note in this question is that the expansion is isothermal and that we have a closed system. This means that the expansion must happen at a constant temperature (isotherma...

Answered by James L. • Physics tutor

2237 Views