Jika sin x = 3/5 dan x lancip, maka nilai sin (x+45 derajat) =

sin (x + 45) = sin x. cos 45 + cos x. sin 45
                 = (3/5)(√2/2) + (4/5)(√2/2)
                 = 3√2/10 + 4√2/10
                = 7√2/10

Trigonometri
SMA kls X

sin x = 3/5 dan x lancip,
Cos x = 4/5 》 ( 4 => √25-9 )

sin (x+45 derajat)
=sin x cos45 + cos x sin 45
=(3/5 × 1/2×√2 )+(4/5 × 1/2×√2)
= 3/10√2+ 4/10√2
= 7/10 √2