Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
In a triangle $\mathrm{ABC}$ if $\mathrm{a}=2, \mathrm{~b}=3$ and $\sin \mathrm{A}=\frac{2}{3}$, then what is angle B equal to?
MathematicsProperties of TrianglesNDANDA 2018 (Phase 1)
Options:
  • A $\frac{\pi}{4}$
  • B $\frac{\pi}{2}$
  • C $\frac{\pi}{3}$
  • D $\frac{\pi}{6}$
Solution:
2358 Upvotes Verified Answer
The correct answer is: $\frac{\pi}{2}$
In $\Delta \mathrm{ABC}, \mathrm{a}=2, \mathrm{~b}=3$ and $\sin \mathrm{A}=\frac{2}{3}$
We know, $\frac{\sin A}{a}=\frac{\sin B}{b}$
$\Rightarrow \frac{\frac{2}{3}}{2}=\frac{\sin B}{3}$
$\Rightarrow \frac{2}{6}=\frac{\sin B}{3} \Rightarrow \sin B=\frac{6}{6}=1$
$\Rightarrow B=\sin ^{-1}(1)$ ...(1)
$=\frac{\pi}{2}$.

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.