In the triangle ABC, AB = 5 cm, BC = 6 cm and area of triangle is 11.25 cm². What is the value of angle ∠ABC?
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সঠিক উত্তরঃ
C.
sin^-1(3/4)
Explanation:

Another Explanation (5): ```html
Let \(a\), \(b\), and \(c\) be the lengths of sides BC, AC, and AB respectively. Let \(A\) be the area of the triangle.
Given: \(c = AB = 5\) cm, \(a = BC = 6\) cm, and \(A = 11.25\) cm².
We want to find the angle ∠ABC, which we can denote as \(B\).
The area of a triangle can be expressed as:
\[A = \frac{1}{2}ac\sin(B)\]
Plugging in the given values:
\[11.25 = \frac{1}{2} \times 6 \times 5 \times \sin(B)\]
\[11.25 = 15 \sin(B)\]
\[\sin(B) = \frac{11.25}{15}\]
\[\sin(B) = \frac{1125}{1500}\]
\[\sin(B) = \frac{225}{300}\]
\[\sin(B) = \frac{45}{60}\]
\[\sin(B) = \frac{3}{4}\]
Therefore,
\[B = \sin^{-1}\left(\frac{3}{4}\right)\]
So, the angle ∠ABC is \(\sin^{-1}(\frac{3}{4})\). 🎉
```