Let's denote the first term of the arithmetic progression as 'a' and the common difference as 'd'.
The third term can be expressed as:
a + 2d = 9 ------(1)
Similarly, the 11th term can be expressed as:
a + 10d = -7 ------(2)
To solve this system of equations, we can subtract equation (1) from equation (2):
(a + 10d) - (a + 2d) = -7 - 9
8d = -16
Dividing both sides of the equation by 8, we get:
d = -2
Substituting this value of d into equation (1), we can solve for a:
a + 2(-2) = 9
a - 4 = 9
a = 9 + 4
a = 13
Therefore, the first term of the arithmetic progression is 13.
The third term of an A.p. is 9 while the 11th term is -7, find the first terms of the A.
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