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Tamil Nadu Board of Secondary EducationHSC Science Class 11

In a ∆ABC, if a = 12 cm, b = 8 cm and C = 30°, then show that its area is 24 sq.cm - Mathematics

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Question

In a ∆ABC, if a = 12 cm, b = 8 cm and C = 30°, then show that its area is 24 sq.cm

Sum

Solution


In ∆ABC Given

a = 12 cm,

b = 8 cm,

C = 30°

Area ∆ = `1/2` ab sin C

= `1/2 xx 12 xx 8 xx sin 30^circ`

= `6 xx 8 xx 1/2`

= 6 × 4

= 24 sq.cm

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Chapter 3: Trigonometry - Exercise 3.10 [Page 146]

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Samacheer Kalvi Mathematics - Volume 1 and 2 [English] Class 11 TN Board
Chapter 3 Trigonometry
Exercise 3.10 | Q 5 | Page 146

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