document.write( "Question 890240: If angle θ is an acute angle such that cosθ = 1/4, find tan (theta/2). \n" ); document.write( "
Algebra.Com's Answer #538861 by lwsshak3(11628)\"\" \"About 
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If angle θ is an acute angle such that cosθ = 1/4, find tan (theta/2).
\n" ); document.write( "sinθ=√1-cos^2θ=√(1-1/16)=√(15/16)=√15/4
\n" ); document.write( "Identity: tan(θ/2)=sinθ/(1+cosθ)=√15/4/(1+1/4)=√15/4/(5/4)=√15/5
\n" ); document.write( "..
\n" ); document.write( "Check:
\n" ); document.write( "cosθ=1/4
\n" ); document.write( "θ≈75.52˚
\n" ); document.write( "θ/2≈37.76˚
\n" ); document.write( "tan(θ/2)=tan(37.76)≈0.7746…
\n" ); document.write( "Exact value=√15/5≈0.7746… \n" ); document.write( "
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