Question

if n be odd or even then the sum of n terms of the series 1-2+3-4+5-6 will be

Answer 1

given (taking two consecutive terms together)
a₁=-1
a₂=-1
a₃=-1
d=0
aₙ=-1×-1×............ⁿ ᵗⁱᵐᵉˢ ×-1
aₙ=1;when n is even
and
aₙ=-1 ; When n is odd

Answer 2

Answer:

q. 6 is your answer