Exercise 3 Page 80

We will begin by finding the pattern. Then, we will be able to find the next two numbers.

By observing the given sequence, we can see that there is no common difference nor common ratio.

1 \to - 3 - 2 \to + 5 3 \to - 7 - 4 \to + 9 5 1 ⟶ \times (- 2) - 2 ⟶ \times (- \frac{2}{3}) 3 ⟶ \times (- \frac{4}{3}) - 4 ⟶ \times (- \frac{5}{4}) 5

This means that we have to take a different approach. First, note that the signs alternate from positive to negative.