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I have a problem that says : express sin11pi/12+sin5pi/12 as a product and find the exact value of the product I have no clue aout this problem I was wondering could you work this out and show me how u did it please
Let's use the Trigonometric Identity :
sin(α)cos(β)=(½)[sin(α+β)+sin(α-β)]
In our case α=8 & β=3 . Thus,
sin(11π/12)+sin(5π/12)=2sin(2π/3)cos(π/4)=2sin(2π/3)sin(π/4) because
sin(π/4)=cos(π/4)=1/√2 & sin(2π/3)=√3/2. So,
sin(11π/12)+sin(5π/12)=2*(1/√2)*(√3/2)=)=√(3/2)=√3/√2 .
Alon.
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Alon Mandes
Expertise
Kind of questions I can answer : Limits, Derivatives, Integration, Implicit functions, continuousity, differentiation ,Extremum problems, Lagrange multipliers, Gradients, Surface integrals, Multi variables functions ,Multi variables Integrals,Complex variables ,Complex functions, Curves, Trajectory integrals & Vector analyse,Divergence,Rotor & word problems. Kind of question I can't answer : Economics,Combinatorics,infinite series & convergence ,Statistics & Probabilities .
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1. I'm a team member of mathnerds (math site for answering questions)
2. I'm a team member in the Student's Union of the Technion, helping
students who have problems in mathematics.
3. 2 years of experience as a math teacher in college.
4. I give free homework help for high school students in
Mathematics & Physics.
5. I teach part time in collage the subjects : "Digital Signal Processing" , "Random Signals & Noise" ,
"Complex Functions".
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Hi-Tech company : GSM4VOIP ; job possition : Algorythm developer.
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M.A in Mathematics & Bs.c in Electronics.
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