Question

in an AP ,if a2=7.3/4,a29=1,an=-6.1/2,then n=?

Answer 1

Answer:

an=a+(n-1)d

Step-by-step explanation:

a2=a+(2-1)d

7.3/4=a+d. ....I

again

a29=a+(29-1)d

1=a+28d......ii

from I and ii

7.3/4=a+d

1=a+28d

changing sign

- - -

a and a cancel

7.3/4-1=d-28 d

0.825=-27d

d=0.825/27

d=0.03555

substituting value of d in I

7.3/4=a+0.03055

a=-1.7944

now an= a+(n-1)d

-6.1/2=1.7944+(n-1)0 .0355

*solve it *

mark me as brainleist