document.write( "Question 741139: Evaluate sin(arccos 4/5 + arctan 2) Let A = arccos 4/5 and B = arctan 2.\r
\n" ); document.write( "\n" ); document.write( "Please help :) \n" ); document.write( "
Algebra.Com's Answer #451895 by lwsshak3(11628)\"\" \"About 
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Evaluate sin(arccos 4/5 + arctan 2) Let A = arccos 4/5 and B = arctan 2.
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\n" ); document.write( "let o=opposite side
\n" ); document.write( "let a=adjacent side
\n" ); document.write( "let h=hypotenuse
\n" ); document.write( "..
\n" ); document.write( "cos(A)=4/5=a/h
\n" ); document.write( "a=4, h=5
\n" ); document.write( "o=√(h^2-a^2)=√(25-16)=√9=3
\n" ); document.write( "sin(A)=o/h=3/5
\n" ); document.write( "..
\n" ); document.write( "tan(B)=2=o/a
\n" ); document.write( "o=2, a=1
\n" ); document.write( "h=√a^2+o^2)=√(1+4)=√5
\n" ); document.write( "cos(B)=a/h=1/√5
\n" ); document.write( "sin(B)=o/h=2/√5
\n" ); document.write( "..
\n" ); document.write( "sin(arccos 4/5 + arctan 2)=sin(A+B)=sin(A)cos(B)+cos(A)sin(B)
\n" ); document.write( "=(3/5)*(1/√5)+(4/5)*(2/√5)=3/5√5+8/5√5=11/(5√5)
\n" ); document.write( "..
\n" ); document.write( "Calculator check:
\n" ); document.write( "cosA=4/5
\n" ); document.write( "A=36.87º
\n" ); document.write( "tanB=2
\n" ); document.write( "B=63.43
\n" ); document.write( "A+B=100.30º
\n" ); document.write( "sin(A+B)=sin(100.30º)=0.9839..
\n" ); document.write( "11/(5√5)=0.9839.. \n" ); document.write( "
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