Mathematical Treasure-hunt: Sine & Cosine

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Mathematical Treasure-hunt: Sine & Cosine

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The area of a triangle is 10 sq cm. The angle

between two of the sides of length 6 cm and 8 cm resp. are obtuse. Work

out the size of this angle.

In the triangle below work out the value of the

area.5 cm3 cm

40

2.966.66

Mathematical Treasure-hunt: Sine & Cosine

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Mathematical Treasure-hunt: Sine & Cosine

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Triangle ABC is such that AB = 4cm, BC = 6 cm and angle ACB = 36. Find the

length AC.

The sides of a triangle are 3,5

and 7 cm. Show that the

largest angle is 120 and find

the area.

13.7 11.2

Mathematical Treasure-hunt: Sine & Cosine

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Mathematical Treasure-hunt: Sine & Cosine

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From a point A a boat sails due north for 7 km to B. The

boat leaves B and moves on a bearing of 100 for 20 km until

it reaches C. calculate the distance C from A.

A triangle has sides AB = 4.5 cm, BC = 6.8 cm and angle

ACB = 30. Find the largest angle.

6.50 22.3

Mathematical Treasure-hunt: Sine & Cosine

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Mathematical Treasure-hunt: Sine & Cosine

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In triangle ABC AB = 5 cm , BC = 6 cm and AC = 10 cm. Calculate the value of

the largest angle.

A helicopter flies on a bearing of 080

from A to B where AB = 50km.It then flies for 60 km to a point C. Given that C is 80 km from A calculate

the bearing of C from A.

101 or 131 104

Mathematical Treasure-hunt: Sine & Cosine

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Mathematical Treasure-hunt: Sine & Cosine

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In triangle ABC AB = 9.3, BC = 6.2 and AC = 12.7. calculate the value of the

largest angle.

The lengths of a triangle are in the ratio 2:3:4. calculate the largest

angle.

128.5 or 31.5 108.4