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In a DeltaABC, if A=45^(@), b=sqrt(6), a...

In a `DeltaABC`, if `A=45^(@)`, `b=sqrt(6)`, a=2, then B=

A

`30^(@)or150^(@)`

B

`60^(@)or120^(@)`

C

`45^(@)or135^(@)`

D

none of these

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The correct Answer is:
To solve the problem, we will use the Sine Rule in triangle ABC, where we know angle A, side a, and side b. ### Step-by-Step Solution: 1. **Write down the Sine Rule**: The Sine Rule states that: \[ \frac{\sin A}{a} = \frac{\sin B}{b} = \frac{\sin C}{c} \] Here, we will focus on the first two parts of the equation. 2. **Substitute the known values**: We know: - \( A = 45^\circ \) - \( a = 2 \) - \( b = \sqrt{6} \) Thus, we can write: \[ \frac{\sin 45^\circ}{2} = \frac{\sin B}{\sqrt{6}} \] 3. **Calculate \(\sin 45^\circ\)**: We know that: \[ \sin 45^\circ = \frac{1}{\sqrt{2}} \] Substituting this value into the equation gives: \[ \frac{\frac{1}{\sqrt{2}}}{2} = \frac{\sin B}{\sqrt{6}} \] 4. **Simplify the left side**: The left side simplifies to: \[ \frac{1}{2\sqrt{2}} = \frac{\sin B}{\sqrt{6}} \] 5. **Cross-multiply**: Cross-multiplying gives: \[ \sin B = \frac{\sqrt{6}}{2\sqrt{2}} \] 6. **Simplify \(\frac{\sqrt{6}}{2\sqrt{2}}\)**: We can simplify this further: \[ \sin B = \frac{\sqrt{3} \cdot \sqrt{2}}{2\sqrt{2}} = \frac{\sqrt{3}}{2} \] 7. **Find angle B**: We know that: \[ \sin B = \frac{\sqrt{3}}{2} \] This corresponds to: \[ B = 60^\circ \quad \text{or} \quad B = 120^\circ \] ### Final Answer: Thus, the possible values for angle B are \( 60^\circ \) or \( 120^\circ \). ---
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