EM-3061

Cosine rule

E Math · Secondary 4 · Medium · Cosine rule

In triangle PQR,

PQ=8\text{ cm}

and

PR=11\text{ cm}

. The included angle

\angle QPR=47^\circ

. Using the Cosine Rule, find the length of side

QR

correct to 3 significant figures.

8.06 cm
6.49 cm
9.41 cm
12.9 cm

Sign in to check your answer and see the hint and the worked explanation. Free on PrepLab High.

Loading problem…