Find the sum of each of the following Aps:
(i) 2, 7, 12, 17, … to 19 terms
(ii) 9, 7, 5, 3,…. To 14 terms.
(iii) -37, -33, -29,… to 12 terms
(iv) `(1)/(15), (1)/(12), (1)/(10),… ` to 11 terms.
(v) 0.6, 1.7, 2.8, …. to 100 terms
Correct Answer - B
`(b)` Let `A=[{:(a,b,c),(p,q,r),(x,y,z):}]`
Given `{:(a+b+c=1),(p+q+r=1),(x+y+z=1):}`
`impliesA^(2)=[{:(a,b,c),(p,q,r),(x,y,z):}][{:(a,b,c),(p,q,r),(x,y,z):}]`
`=[{:(a^(2)+bp+cx,,ab+bq+cy,,ac+br+cz),(pa+qp+rx,,qb+q^(2)+ry,,pc+qr+rz),(xa+yp+zx,,xb+yq+zy,,xc+yr+z^(2)):}]`
Sum of elements of
`R_(1)=a^(2)+bp+cx+ab+bq+cy+ac+br+cz`
`=a(a+b+c)+b(p+q+r)+c(x+y+z)`
`=a+b+c=0`
Similarly sum of elements of
`R_(2)=p(a+b+c)+q(p+q+r)+r(x+y+z)`
`=p+q+r=1`
`R_(3)=x(a+b+c)+y(p+q+r)+z(x+y+z)`
`=x+y+z=1`
`:.` sum of element...