(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Let A,B,C be three angles such that A=45 (degrees) and tanBtanC=p. Find all possible values of p such that A,B,C are the angles of a triangle.

2. Relevant equations

3. The attempt at a solution

I got an expression for cos(B-C)= (1+p)/{(p-1)√2}

My book says this-

Since B or C can vary from 0 to 135,

-1/√2 < (1+p)/{(p-1)√2} <= 1

I did not understand how this step came. Please help

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# Homework Help: Trigonometry (identitites)

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