# Exam Tips

### Memorize key Facts

#### Trigonometry Exact Values

You definitely need to know these before paper 1.

#### Graphs of Sine Cosine and Tangent Functions

Ensure that you know how to sketch these graphs so that you can work out the key properties of the functions

Some students like to use the following diagram to remind them in which quadrants each of the trigonometric ratios is positive

#### Chain Rule

You should know how to use the Chain Rule to differentiate a composite function, but you are sometimes required to know the general form when the question is given in function notation. This is not in the formula booklet

$$h(x)=f[g(x)]\\ h'(x)=g'(x)f'[g(x)]$$

This is useful for answering exam questions like the following

There are other formula that are derived from the Chain Rule. It helps your speed if you can memorize these

Need some practice in using these? Why not try a quiz from  Chain Rule page

#### Integration by Recognition

These integrals can all be found by integration by substitution, but if you can recognize them, you can save yourself a lot of time

#### Properties of Vector Product

There are several properties of the vector product that do not appear in the formula booklet

#### Properties of Complex Numbers

There are several properties of complex numbers that do not appear in the formula booklet

### Timing

##### How do you ensure that you make best use of time during the examination?

In the examinations, you are given 5 minutes reading time. Many students don't like, nor make good use of, this time. Quickly glancing at unfamiliar questions can cause panic. Don't forget that this 5 minutes is a bonus, so make the most of it! You are not allowed to write anything down during this time, but it is useful for helping you organise yourself, gather your thoughts and decide on a plan for the examination that follows. In your revision, you should practise papers under timed conditions and include this reading time to decide how best to use it. Here are some suggestions as to how you might use it
• Quickly glance through the paper and check that you there are not any missing questions or pages. This should also enable you to not miss out any questions and avoid that OMG, I didn't see that last page!
• Find some questions that you like the look of and start thinking about how you might start them.
• There will be some unfamiliar questions. Try not to panic. Once you have got warmed up, you will be in a better position to try them.
• Take a few deep breaths.

The examination is divided into two sections: section A (write on the paper), section B (write in the booklet). The marks available for the two sections are approximately equal, so you should divide your time equally between them. Many students spend too long on section A and run out of time on section B. The questions in section A gradually increase in difficulty and the last question in section A is for superhuman students who are aiming at a high grade 7. Do not spend too much time on this question and be prepared to leave it out (you can always come back to it at the end). Which would you rather do: the last question in section A worth 6-8 marks or the last question in section B worth 18-24 marks?

### Command Terms

#### Show that vs Verify

The term show that comes up in long section B questions, it is there to help you. First of all, you know the answer that you are trying to attain and secondly, if you are unable to get the answer, you can carry on with the next part using the answer given in the question. In questions that require you to show that you must try to avoid working backwards from the answer.

A question that asks you to verify requires only for you to provide evidence that validates a result, perhaps by substituting a value into a formula.

Here are two examples that should help you to see what to do:

#### Sketch vs Plot

In questions that ask you to sketch, you are not expected to draw an accurate plot of a graph using graph paper. You need to include key information: local maxima/minima, intercepts and equations of asymptotes.

In questions asking you to plot, you are often required to mark the position of points on a diagram.

Here is an example to show you what might be expected in a question asking you to sketch a graph of a function:

#### Hence

The word hence is there to help you. You should be using something that you found in the previous part to help you find the answer to this question. If you ignore this, not only do you risk wasting time, but also marks, since using a different method may get you no marks!

Here is an example:

#### Hence or otherwise

This is very much like hence, but is meant more for guidance. The previous part of a question may guide you to use a particular method, this may be the quickest and most obvious method. However, you will not be penalised if you use an alternative method.

#### Write down

This means you probably won't have to do any working out (or not much at least). You should be able to complete this fairly quickly.

### Accuracy

##### Unless otherwise stated in the question, all numerical answers should be given exactly or correct to three significant figures.

On paper two, you risk losing several marks if you do not round your answers appropriately. According to the reports by examiners, some students don't seem to know the difference between rounding to 3 decimal places and rounding to 3 significant figures. This is an easy one to get right!

Here's a recap of significant figures if you need it:

• Significant figures are a way of rounding numbers that allow you to always be consistent in the accuracy of your answers.
• The first significant figure is the first non-zero digit.
• Start counting significant figures after this digit.
• Any zeros between non-zero digits are significant.
• Stop counting (for 3 sig figs) when you get to the third significant figure
• Decide to round up or down

#### Example 1

0.00305

The 1st significant figure is 3

The 2nd significant figure is 0 (the zero between 3 and 5 is SIGNIFICANT)

The 3rd significant figure is 5

#### Example 2

Round the following numbers to 3 significant figures

a) 82 761 $$\approx$$ 82 800

b) 0.001358 $$\approx$$0.00136

c) 57.0098 $$\approx$$ 57.0

### Graphical Calculator Skills

##### Every year students lose easy marks because they don't know how to use their graphical calculators. Here is some advice for using your graphical calculator in paper 2.

• Make sure that your calculator has the latest operating system/firmware and you know how to put it in examination mode (press to test). You should practise using it in this mode to avoid any surprises.
• Students often use an analytical method and waste time when they should use their calculators. Once an equation is set up, use your calculator to solve it.
• Several marks for a question suggests working out needs to be shown.
• Sketch the output of graphing screen to show key features which lead to answer. Don't forget to label axes.
• Round only at end of the question, that is, use more than 3 significant figures in calculations. Better still, know how to use calculator memory.

### Miscellaneous

##### Here are some final top tips for maximising your performance in the examinations

• Read the questions carefully. Underline key terms. This will slow you down and allow you to think and may give you a clue as to how to solve the problem.
• Write down as much information as you can. In the question below, you are given credit for recognising that it is a question about binomial probabilities. Write down all your thinking!