Squares, roots and powers

2.3.1 Try some yourself

Activity 22

Write the following as one number to a single power:

  • (a) 23 × 24

  • (b) 32 × 34

  • (c) 42 × 43 × 44

Answer

  • (a) 23 × 24 = 2(3 + 4) = 27

  • (b) 32 × 34 = 3(2 + 4) = 36

  • (c) 42 × 43 × 44 = 4(2 + 3 + 4) = 49

Activity 23

Without using your calculator, find the following, as estimates for calculation work in the next question.

  • (a) (1)5

  • (b) 34

Answer

  • (a) (1)5 = 1 (any odd power of 1 is 1)

  • (b) 34 = 3 × 3 × 3 × 3 = 81

Activity 24

Use your calculator to find the following.

  • (a) (1.3)5

  • (b) 3.24

(Use your answers to the previous question as rough checks.) Round your answers to four decimal places.

Answer

  • (a) (1.3)5 3.7129

  • (b) 3.24 = 104.8576