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September 16, 2014

September 16, 2014

Posted by **Natash** on Saturday, November 15, 2008 at 2:40am.

Sin(11pi/8)

so this is sin(pi/4+pi/3)

sin(pi/4)*cos(pi/3)+cos(pi/3)*sin(pi/4)

rad2/2*1/2+1/2*rad2/2

which gives me rad2+rad2 all over 4 ...i dont know y im getting it wrong

- trig -
**drwls**, Saturday, November 15, 2008 at 5:09ampi/4 + pi/3 does NOT equal 11 pi/8

It equals 7 pi/12

sin (11pi/8) = -sin3pi/8

= -sin[(1/2)3pi/4]

Now use the "sine half angle" formula

= -sqrt[(1/2)(1-cos3pi/4)]

= -sqrt[(1/2)(1+(sqrt2)/2)]

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