Pada segitiga PQR, siku-siku di Q, PR + QR = 25 cm, dan PQ = 5 cm. Hitung nilai sin P, cos P, dan tan P.
Pembahasan:
PR2 = PQ2 + QR2
(25 – x)2 = 52 + x2
625 – 50x + x2 = 25 + x2
600 = 25x
x = 12
QR = 12
PR = 25 – x = 25 – 12 = 13
sin P = QR/PR = 12/13
cos P = PQ/PR = 5/13
tan P = QR/PQ = 12/5
