13. If y = (1 + tan A) (1 - tan B), where `A -B=pi/4` then `(y+ 1)^(y + 1)` is equal to

If y = (1 + tan A) (1 - tan B), where A -B=pi/4 then (y+ 1)^(y + 1) is equal to ............ A) 9 B) 4 C) 27 D) 81

If y=(1+t a n A)(1-t a n B), where A-B=pi/4, then (y+1)^(y+1) is equal to

Ify = (1 + tan.4) (1-tan B), where AB = (pi) / (4) (y + 1) ^ (y + 1) i sequalt

If y= (1+ tan A) (1- tan B) where A-B =pi/4, then the value of (y+1) ^(y+1) is-

If y=(1+tan A)(1-tan B), where A-B=(pi)/(4), then (y+1)^(y+1) is equal to 9 (b) 4(c)27(d)81

tan^(-1)x+tan^(-1)y is equal to

If A+B=(pi)/(4), then (tan A+1)(tan B+1) equals

If tan ^(-1) x + tan ^(-1) y + tan ^(-1) z = (pi)/(2), then xy + yz+zx is equal to

If tan^(-1)x+tan^(-1)y=(pi)/(4), then (1+x)(1+y) is equal to