in triangle PQR, PQ = a, QR = a + d, RP = a + 2d, and angle PQR is more than 120 degree., where a and d are positive constants. show that(adsbygoogle = window.adsbygoogle || []).push({});

2a/3 < d < a.

i tried to think, but i really dont know how to start to solve this question. hope for some clue.

thank you

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# Homework Help: Trigonometry homework help question

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