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प्रश्न
In the given figure, ΔPQR is a right triangle right angled at Q. If PQ = 4 cm and PR = 8 cm, then P is ______.
पर्याय
60°
45°
30°
15°
उत्तर
In the given figure, ΔPQR is a right triangle right angled at Q. If PQ = 4 cm and PR = 8 cm, then P is 60°.
Explanation:
cos P = `(PQ)/(PR)`
= `4/8`
= `1/2`
cos P = cos 60°
`\implies` P = 60°
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