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if cosA=(-7/25) and sinB=(4/5), with A in QIII and B in QII, find the exact value of the following expressions please and thank you!!
\n" ); document.write( "sin(B/2)
\n" ); document.write( "sin(A+B)
\n" ); document.write( "cos^2(B/2)
\n" ); document.write( "tan(A-B)
\n" ); document.write( "**
\n" ); document.write( "In QIII, cos and sin<0, tan>0
\n" ); document.write( "cosA=-7/25=adj side/hypotenuse
\n" ); document.write( "opp side=-√(25^2-7^2)=-√(625-49)=-√576=-24
\n" ); document.write( "sinA=opp side/hypotenuse=-24/25
\n" ); document.write( "tanA=opp side/adj side=-24/-7=24/7
\n" ); document.write( "..
\n" ); document.write( "In QII, cos and tan<0, sin>0
\n" ); document.write( "sinB=4/5 (you are working with a 3-4-5 right triangle)
\n" ); document.write( "cosB=-3/5
\n" ); document.write( "tanB=-4/3
\n" ); document.write( "..
\n" ); document.write( "Identity: sin(x/2)=±√[(1-cosx)/2]
\n" ); document.write( "sin(B/2)=√[(1-cosB)/2]
\n" ); document.write( "=√[(1-(-3/5))/2]
\n" ); document.write( "=√[(1+3/5)/2]
\n" ); document.write( "=√[8/5)/2]
\n" ); document.write( "=√[8/10]
\n" ); document.write( "=√.8
\n" ); document.write( "..
\n" ); document.write( "Identity: sin(A+B)=sinA cosB+cosA sinB
\n" ); document.write( "=(-24/25)*(-3/5)+(-7/25)*(4/5)
\n" ); document.write( "=(72/125)-28/125
\n" ); document.write( "=44/125
\n" ); document.write( "..
\n" ); document.write( "B/2=±√[(1+cosB)/2]
\n" ); document.write( "cos^2(B/2)=(1+cosB)/2=(1+(-3/5))/2=(2/5)/2=2/10=0.2
\n" ); document.write( "..
\n" ); document.write( "tan(A-B)=(tanA-tanB)/(1+tanA tanB)
\n" ); document.write( "I will let you do this one \n" ); document.write( "