Earth - earth is the only planet in our solar system's habitable zone. Mercury and Venus are not in the habitable zone because they are too close to the Sun to harbor liquid water. However, evidence suggests that the Sun used to be much dimmer.
What's In In the previous module, it was discussed how to find the nth term of a given arithmetic sequence. The formula an = a₁ + d(n − 1) can be used to find any nth term of any arithmetic sequence. This module will be discussing with you how to find the sum of the terms in an arithmetic sequence. For example, how do we compute the sum of all the terms of each of the following sequences? 1. 1, 2, 3, . . . , 100 2. 5, 10, 15, 20, . . . , 50 3. -5, -2, 1, 4, . . . , 31