" If "18,a,b,-3" are in AP then find "a+b" ."

If 18,a,b,-3 are in AP,then a+b=

If 18, a, (b-3) are in AP, then find the value of (2a-b).

State 'T' for true and 'F' for false . I. A sequence is an A.P ., if and only if the sum of its n terms is of the form An^(2) +Bn , where A and B are constants . II. If 18, a, b , -3 are in A.P., then a+b = 15 . III If a,c,b are in A.P., then 2c=a+b . IV .The n^(th) term from the end of an A.P. is the (m-n+1)^(th) term from the beginning , where m terms are in A.P.

If 18 ,\ a ,\ b ,\ -3 are in A.P., the a+b= (a) 19 (b) 7 (c) 11 (d) 15

If 18 ,\ a ,\ b ,\ -3 are in A.P., the a+b= (a) 19 (b) 7 (c) 11 (d) 15

If a,b , c are in AP, then, find the value of (a-c)^2/(b^2-ac)

1/16 , a and b are in G.P , 1/a,1/b and 6 are in A.P then find 72(a+b)

If a,b,c are in A.P .then 3^a , 3^b and 3^c are in

If a, b, c are in A.P. then 3^a, 3^b, 3^c are in: