The 43rd term of an AP is 26 find the first term of the progression,given its common difference 1/2

Let the first term of the arithmetic progression be 'a' and the common difference be 'd'.

The formula to find the nth term of an AP is:
an = a + (n-1)d
Given that the 43rd term of the AP is 26, we can substitute n = 43 and an = 26 into the formula to get:
26 = a + (43-1)(1/2)
26 = a + 42(1/2)
26 = a + 21
Subtracting 21 from both sides:
5 = a
Therefore, the first term of the arithmetic progression is 5.

To find the first term of an arithmetic progression (AP), we can use the formula:

\[ a_n = a_1 + (n-1)d \]

where:
- \(a_n\) is the \(n\)th term of the AP
- \(a_1\) is the first term of the AP
- \(d\) is the common difference
- \(n\) is the term number

In this case, we are given that the 43rd term of the AP is 26, and the common difference is \( \frac{1}{2} \). Let's use the formula to find \(a_1\):

\[ 26 = a_1 + (43-1) \left(\frac{1}{2}\right) \]

Simplifying the equation:

\[ 26 = a_1 + 42 \left(\frac{1}{2}\right) \]

\[ 26 = a_1 + 21 \]

Now, let's isolate \(a_1\):

\[ a_1 = 26 - 21 \]

\[ a_1 = 5 \]

Therefore, the first term of the arithmetic progression is 5.

To find the first term of an arithmetic progression (AP), we can use the formula:

nth term = first term + (n - 1) * common difference

Here, the given information is the 43rd term of the AP, which is 26, and the common difference is 1/2.

Let's substitute these values into the formula:

26 = first term + (43 - 1) * (1/2)

To simplify, we'll calculate (43 - 1) * (1/2):

42 * (1/2) = 21

The equation now becomes:

26 = first term + 21

To isolate the first term, we'll subtract 21 from both sides of the equation:

26 - 21 = first term

5 = first term

Therefore, the first term of the AP is 5.