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Question
In ΔABC right angled at B, AB = 24 cm, BC = 7 m. Determine:
sin A, cos A
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Solution
ΔABC is right angled at B
AB = 24 cm, BC = 7 cm
Let ‘x’ be the hypotenuse,
By applying Pythagoras
AC2 = AB2 + BC2
x2 = 242 + 72
x2 = 576 + 49
x2 = 625
x = 25
For Sin A, Cos A
At ∠A, opposite side = 7
adjacent side = 24
hypotenuse = 25
sin A = `"opposite side"/"hypotenuse" =("BC")/("AC") = 7/25`
cos A = `"adjacent side"/"hypotenuse" = ("AB")/("AC") = 24/25`
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