Find the sine cosine and tangent of the half angle 2 based o

Find the sine, cosine and tangent of the half angle /2, based on the given information on . Use exact values.

#10.) tan = 7/24, 3 < < 2

#12.) = arccos(5/13)

Can someone walk me through these 2 problems? I\'m struggling on what to do.

10 . tan = -7/24 , -3pi< < -2pi

is IVrth quadrant

cos = 24/25

Now use th double angle formula:

cos = 2cos^2(/2) -1

cos(/2) = sqrt{(1+cos)/2} = sqrt{(1+24/25)/2} = +/- 7/5sqrt2

cos = 1- 2sin^2(/2)

sin(/2) = sqrt{( 1- cos)/2} = sqrt{(1 -24/25/2} = +/-1/5sqrt2

tan(/2) = sin(/2)/cos(/2) = 1/7

12) = arccos(-5/13)

Range of arccos [0, pi]

cos = -5/13 ; is IInd quadrant

sin = 12/13

cos = 2cos^2(/2) -1

cos(/2) = sqrt{(1+cos)/2} = sqrt( 1+ (-5/13))/2) = 2/sqrt13

sin(/2) = sqrt{(1-cos)/2} = sqrt( 1 -(-5/13))/2) = 3/sqrt13

tan(/2) = sin(/2)/cos(/2) = 3/2