nilai sin 135° - cos 225° + tan 405° =

sin 135 derajat - cos 225 derajat + tan 405 derajat
= sin (180 - 45) derajat - cos (270 - 45) derajat + tan (360 + 45) derajat
= sin 45 derajat - (- cos 45 derajat) + tan 45 derajat
= [1/2 × 2^(1/2)] + [1/2 × 2^(1/2)] + 1
= 2^(1/2) + 1
= 2^(1/2) + [2^(1/2) / 2^(1/2)]
= [(2^(1/2))^2 + 2^(1/2)] / 2^(1/2)
= [2 + 2^(1/2)] / 2^(1/2)
= [2^(1/2) + 2] / 2
= 2^(1/2) + 1