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Trigonometry — Question 301

Original QCE Vault practice · 4 marks

Q301 · Practice questionTechnology-freeComplex familiar4 marks

QUESTION 301 (4 marks)

A triangular sail has side lengths

13

m,

14

m and

15

m. Let

\theta

be the angle between the

13

m and

14

m sides.

Triangle with sides 13,14,15 m; theta is between the 13 and 14 m sides. Not to scale.

a)

Show that

\cos\theta=\dfrac5{13}

.

[2 marks]

b)

Determine the exact area of the sail without using Heron's formula.

[2 marks]

Question linkSyllabus coverage

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