Sunday, June 10, 2012

`(17pi)/12 = (9pi)/4 - (5pi)/6` Find the exact values of the sine, cosine, and tangent of the angle.

`sin(u-v)=sin(u)cos(v)-cos(u)sin(v)`


`sin((9pi)/4-(5pi)/6)=sin((9pi)/4)cos((5pi)/6)-cos((9pi)/4)sin((5pi)/6)`


`sin((9pi)/4-(5pi)/6)=(sqrt2/2)(-sqrt3/2)-(sqrt2/2)(1/2)=-sqrt2/4(sqrt3+1)` 



`cos(u-v)=cos(u)cos(v)+sin(u)sin(v)`


`cos((9pi)/4-(5pi)/6)=cos((9pi)/4)cos((5pi)/6)+sin((9pi)/4)sin((5pi)/6)`


`cos((9pi)/4-(5pi)/6)=(sqrt2/2)(-sqrt3/2)+(sqrt2/2)(1/2)=-sqrt2/4(sqrt3-1)`



`tan(u-v)=(tan(u)-tan(v))/(1+tan(u)tan(v))`


`tan((9pi)/4-(5pi)/6)=(1-(-sqrt3/3))/(1+(1)(-sqrt3/3))=((3+sqrt3)/3)/((3-sqrt3)/3)=(3+sqrt3)/(3-sqrt3)`


After rationalizing the denominator the answer is `2+sqrt3.`

No comments:

Post a Comment

What was the device called which Faber had given Montag in order to communicate with him?

In Part Two "The Sieve and the Sand" of the novel Fahrenheit 451, Montag travels to Faber's house trying to find meaning in th...