# Stage 4 & 5 Toughnuts

### Discriminating

##### Stage: 5

You're invited to decide whether statements about the number of solutions of a quadratic equation is always, sometimes or never true.

##### Stage: 5

This will encourage you to think about whether all quadratics can be factorised and to develop a better understanding of the effect that changing the coefficients has on the factorised form.

##### Stage: 5

In this activity you will need to work in a group to connect different representations of quadratics.

### Picture the Process Ilive

##### Stage: 5

How does the temperature of a cup of tea behave over time? What is the radius of a spherical balloon as it is inflated? What is the distance fallen by a parachutist after jumping out of a plane? After sketching graphs for these and other real-world processes, you are offered a selection of equations to match to these graphs and processes.

### Two-way Functionslive

##### Stage: 5

This gives you an opportunity to explore roots and asymptotes of functions, both by identifying properties that functions have in common and also by trying to find functions that have particular properties. You may like to use the list of functions in the Hint, which includes enough functions to complete the table plus some extras.You might like to work on this problem in a pair or small group, or to compare your table to someone else's to see where you have used the same functions and where not.

### Factorial Fragmentslive

##### Stage: 5 Challenge Level:

Here you have an expression containing logs and factorials! What can you do with it?

### A Big Power

##### Stage: 5 Challenge Level:

Have you ever tried to work out the largest number that your calculator can cope with? What about your computer? Perhaps you tried using powers to make really large numbers. In this problem you will think about how much you can do to understand such numbers when your calculator is less than helpful!

##### Stage: 5 Challenge Level:

A lune is the area left when part of a circle is cut off by another circle. Can you work out the area?

### Can You Find... Trigonometry Edition

##### Stage: 5 Challenge Level:

What graphs can you make by transforming sine, cosine and tangent graphs?

### Equation or Identity (2)live

##### Stage: 5 Challenge Level:

Here are some more triangle equations. Which are always true?

### Staircase Sequences

##### Stage: 5 Challenge Level:

Can you make sense of these unusual fraction sequences?

### Nested Surdslive

##### Stage: 5 Challenge Level:

Can you find values that make these surd statements true?

### Irrational Constructions

##### Stage: 5 Challenge Level:

What questions does the spiral construction prompt you to ask?

### Can You Find... Trigonometric Edition Part 2live

##### Stage: 5 Challenge Level:

Can you find trig graphs to satisfy a variety of conditions?