A triangle has sides in the ratio $1: \sqrt{2}: \sqrt{3}$. If the smallest angle is $\alpha^{\circ}$, what are the other two angles?
A$\sqrt{2}\alpha^{\circ}, \sqrt{3}\alpha^{\circ}$
B$(90-\alpha)^{\circ}, 90^{\circ}$
C$\dfrac{\alpha^{\circ}}{2}, \dfrac{\alpha^{\circ}}{3}$
D$2\alpha^{\circ}, 3\alpha^{\circ}$
Answer & Solution
Correct answer: B. $(90-\alpha)^{\circ}, 90^{\circ}$
Let the sides be proportional to $1,\sqrt{2},\sqrt{3}$, so their squares are $1,2,3$.
Since $1+2=3$, the triangle is right-angled by the converse of the Pythagorean theorem.
The smallest side corresponds to the smallest angle $\alpha^{\circ}$, and the largest side corresponds to $90^{\circ}$.
Therefore the third angle is $180^{\circ}-90^{\circ}-\alpha^{\circ}=(90-\alpha)^{\circ}$.
**Option D is tempting because side sizes increase, but angle measures do not become simple multiples here.**
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