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Question
In ΔABC, if a = 18, b = 24, c = 30 then find the values of sin `(A/2)`.
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Solution
Given:
a = 18, b = 24 and c = 30
∴ 2s = a + b + c
= 18 + 24 + 30
= 72
∴ s = `72/2`
∴ s = 36
`sin (A/2) = sqrt(((s - b)(s - c))/(bc)`
= `sqrt(((36 - 24)(36 - 30))/((24)(30)`
= `sqrt((12 xx 6)/(24 xx 30)`
= `sqrt(1/10)`
= `1/(sqrt10)`
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