Q.5 In Δ ABC , if a = 18 , b = 24 and c = 30 then find the value of sin(A/2) .

Answer: sinA/2 = 1/√(10) s = a + b + c/2 = 18 + 24 + 30/2 = 36 , so s - b = 12 and s - c = 6 . sinA/2 = √((s-b)(s-c)/bc) = √(12 × 6/24 × 30) = √(72/720) = √(1/10) = 1/√(10) .

In \(\Delta ABC\), if \(a = 18\), \(b = 24\) and \(c = 30\) then find the value of \(\sin\left(\frac{A}{2}\right)\).

Q.5 In \(\Delta ABC\), if \(a = 18\), \(b = 24\) and \(c = 30\) then find the value of \(\sin\left(\frac{A}{2}\right)\).

Doubtly Asked 29 Oct 2026 Board exam · March 2024 hsc 12th Save WhatsApp Report

1 answer

Best answer

Answer: \(\sin\frac{A}{2} = \frac{1}{\sqrt{10}}\)

\(s = \frac{a + b + c}{2} = \frac{18 + 24 + 30}{2} = 36\), so \(s - b = 12\) and \(s - c = 6\).

\(\sin\frac{A}{2} = \sqrt{\frac{(s-b)(s-c)}{bc}} = \sqrt{\frac{12 \times 6}{24 \times 30}} = \sqrt{\frac{72}{720}} = \sqrt{\frac{1}{10}} = \frac{1}{\sqrt{10}}\).

Doubtly AI · 29 Oct 2026 AI-generated · not yet verified Report

Was this answer helpful?

In \(\Delta ABC\), if \(a = 18\), \(b = 24\) and \(c = 30\) then find the value of \(\sin\left(\frac{A}{2}\right)\).

1 answer

Your answer