hey i have a problem which im puzzled over. i im given that:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\sin A = \frac{3}{5}[/tex]

and i am asked to find exact values for:

[tex]\sin 2A[/tex]

[tex]\cos 2A[/tex]

[tex]\tan 2A[/tex]

where [tex]90^0 \leq A \leq 180^0[/tex] (the power to zero is the degree sign)

i have gone about solving this by the use of a pythagorien (?) triple, therefore

[tex]\cos A = \frac{4}{5}[/tex] and

[tex]\tan A = \frac{3}{4}[/tex].

however i do not understand how A can be greator than 90 since this is in a right angle triangle. thanks in advance for those who help,

Pavadrin.

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# Homework Help: Trigonometry Identities.

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