Question #77071

1 Answer
Jan 26, 2018

See below..

Explanation:

color(red)((-1)^n(1)n

  • Let, color(red)(n=2mn=2m ; Then," "color(green)((-1)^n=(-1)^(2m)=1^m=1 (1)n=(1)2m=1m=1

CONCLUSION:- When color(red)nn is a even number, color(green)(bar(ul(|color(red)((-1)^(n=2m)=1)|

  • Let, color(red)(n=2m+1 ; Then," "color(green)((-1)^n=(-1)^(2m+1)=(-1)^(2m)xx(-1)^1=1xx(-1)=(-1)

CONCLUSION:- When color(red)n is a odd number, color(green)(bar(ul(|color(red)((-1)^(n=2m+1)=-1)|

Hope it helps...
Thank you...