document.write( "Question 861248: Find tan(s+t) if cos s = (-1/5), sin t = 3/5, and s and t are in quadrant 2.
\n" ); document.write( "I have ready substituted values into the tan sum identity, but I'm having trouble with the arithmetic. \n" ); document.write( "
Algebra.Com's Answer #518929 by lwsshak3(11628)\"\" \"About 
You can put this solution on YOUR website!
Find tan(s+t) if cos s = (-1/5), sin t = 3/5, and s and t are in quadrant 2.
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\n" ); document.write( "\"tan%28s%2Bt%29=%28tan%28s%29%2Btan%28t%29%29%2F%281-tan%28s%29tan%28t%29%29\"
\n" ); document.write( "...
\n" ); document.write( "cos(s)=-1/5
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\n" ); document.write( "tan(s)=sin/cos=-√24/1=-√24
\n" ); document.write( "...
\n" ); document.write( "sin(t)=3/5 (working with a (3-4-5) reference right triangle in quadrant 2)
\n" ); document.write( "cos(t)=-4/5
\n" ); document.write( "tan(t)=sin/cos=-3/4
\n" ); document.write( "...
\n" ); document.write( "\"tan%28s%2Bt%29=%28tan%28s%29%2Btan%28t%29%29%2F%281-tan%28s%29tan%28t%29%29\"
\n" ); document.write( "tan(s+t)=(-√24-3/4)/(1-√24*(3/4)
\n" ); document.write( "...
\n" ); document.write( "calculator check:
\n" ); document.write( "cos(s)=-1/5
\n" ); document.write( "s≈101.54 deg
\n" ); document.write( "sin(t)=3/5
\n" ); document.write( "t≈143.13
\n" ); document.write( "s+t≈244.67
\n" ); document.write( "tan(s+t)=tan(244.67)≈2.112…
\n" ); document.write( "exact value as calculated=(-√24-3/4)/(1-√24*(3/4)≈2.112...
\n" ); document.write( "note: let me know if my solution is correct, helpful and understandable\r
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