Required Prior Knowledge

Questions

Without using your calculator, evaluate the following:

a) \(\left(-1\right)^{5} \)

b) \(\left(-1\right)^{6}\)

c) \(\left(-1\right)^{14}\)

d) \(\left(-1\right)^{19}\)

e) \(\left(-1\right)^{8}\)

f) \(-1^{8}\)

g) \(-\left(-1\right)^{8}\)

h) \(\left(-2\right)^{5}\)

i) \(-2^{5}\)

j) \(-\left(-2\right)^{6}\)

k) \(\left(-5\right)^{4}\)

l) \(-\left(-5\right)^{4}\)

Solutions

Get Ready

Questions

Find the values of \(3^{1},3^{2},3^{3},3^{4},3^{5},…\)

Look for patterns.

Hence find the last digit of \(3^{101}\).

Solutions

Notes

The laws of indices (or exponents or powers) are a set of rules that tell us how to work with indices in order to simplify expressions. These are considered prior knowledge, but a summary is given below. This includes examples and non-examples (common mistakes) for each rule.

Examples and Your Turns

Your Turn

Evaluate each of these using the laws of indices:

a) $$\left(\frac{27}{8}\right)^{\frac{2}{3}}$$

b) $$144^{-\frac{1}{2}}$$

c) $$-125^{\frac{1}{3}}$$

Your Turn

Simplify the expression$$\frac{20\times 9^{2n+1}}{5\times 3^{4n+1}}$$

Your Turn

Simplify the expression$$\left(\frac{a^{\frac{2}{3}}\sqrt{b^{-1}}}{b\sqrt[3]{a^{-2}}}\div \sqrt{\frac{a\sqrt{b^{-4}}}{b\sqrt{a^{-2}}}}\right)^{6}$$

Your Turn

Simplify the expression$$\left(\frac{a^{p-q}}{\sqrt[q]{a^{q^{2}-pq}}}\times a^{2\left(p-q\right)}\right)^{n}$$

Your Turn

Simplify the expression$$\left(x^{\frac{a}{b}y^{-1}}\right)^{b}\div \left(\frac{x^{a^{2}-b^{2}}}{y^{ab+b^{2}}}\right)^{\frac{1}{a+b}}$$

Your Turn

Simplify the expression$$\left(\frac{x^{-2}y^{3}}{x^{3}y^{-2}}\right)^{\frac{1}{5}}\times \left(\frac{y^{3}x^{-3}}{x^{3}y^{-3}}\right)^{-1}$$

Your Turn

Simplify the expression$$\left(\frac{y^{-3}}{x^{\frac{2}{7}}z^{-1}}\right)^{-\frac{3}{2}}\times \left(\frac{y^{\frac{14}{3}}x^{-1}}{z^{-\frac{21}{4}}}\right)^{\frac{2}{7}}$$

Your Turn

Simplify the expression$$\frac{2^{n}\times \left(2^{n-1}\right)^{n}}{2^{n+1}\times 2^{n-1}}\times \frac{1}{4^{-n}}$$

Your Turn

Simplify the expression$$\frac{2^{n+1}}{\left(2^{n}\right)^{n-1}}\div \frac{4^{n+1}}{\left(2^{n-1}\right)^{n+1}}$$

Example

Factorise$$2^{n+3}+2^{n}$$

Your Turn

Factorise $$9^{x}+4\left(3^{x}\right)+4$$

Example

Solve$$3^{x}=3^{1-x}=4$$

Your Turn

Solve $$4^{x}+2^{x}-20=0$$

Key Facts

Use this applet to generate a prompt for a Key Fact that you need to know for the course. The idea is that you should KNOW these key facts in order to be able to solve problems.