1) given that A is obstuse and that sinA=2/(sqaureroot of 5). find the value of cosA and tanA.(adsbygoogle = window.adsbygoogle || []).push({});

2)given that tanA=-5/12 and that tanA and cosA have opposite signs, find the values of sinA and of cosA.

CAN SOMEONE TEACH ME EXACTLY HOW TO DO THESE PROBLEMS WITHOUT USING TRGNOMETRIC IDENTITES.PLEASE....I AM NEW TO THIS TOPIC AND I WANT TO GET A HEADSTART OVER MY PEERS.

THANKS A LOT

VIJAY

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# Obstuse trignometry

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