Question

23. The common difference of an A.P. 6, then
a15 - a11​

Answer 1

Answer:

24

Step-by-step explanation:

we know that

$a_{n}$ = a + (n-1)*d

⇒$a_{15}$ = a + (15-1)*d = a + 14*d

⇒$a_{11}$ = a + (11-1)*d = a + 10*d

∴ $a_{15} - a_{11}$ = a + 14d - (a + 10d)

                 = a + 14d - a - 10d

                 = 4d = 4*6 = 24   ( since d = 6 )