Mmm,
first α2 is between 45 and 67.5 degrees. so that is the first quadrant. All trig ratios are positive
so α must be between 90 and 135 degrees so that is the second quadrant. Only sine and cosec are positive all other ratios will be negative,
Now
\\cos \left(\frac{\alpha}{2}\right)=\frac{5}{8}\\\\ cos^2 \left(\frac{\alpha}{2}\right)=\frac{25}{64}\\\\ cos^2 \left(\frac{\alpha}{2}\right)+sin^2 \left(\frac{\alpha}{2}\right)=1}\\\\ \frac{25}{64}+sin^2 \left(\frac{\alpha}{2}\right)=1}\\\\ sin^2 \left(\frac{\alpha}{2}\right)=1-\frac{25}{64}\\\\ sin^2 \left(\frac{\alpha}{2}\right)=\frac{39}{64}\\\\ sin \left(\frac{\alpha}{2}\right)=\frac{\sqrt{39}}{8}\\\\\\
sin(α)=sin(α2+α2)sin(α)=2sinα2cosα2sin(α)=2∗√398∗58sin(α)=√394∗58sin(α)=5√3932Cosec(α)=325√39Cosec(α)=32√395∗39Cosec(α)=32√39195
cos(α)=cos(α2+α2)cos(α)=cos2(α2)−sin2(α2)cos(α)=2564−3964cos(α)=−1464cos(α)=−732sec(α)=−327
\\tan(\alpha)=sin(\alpha)}\div{cos(\alpha)}\\\\ tan(\alpha)=\frac{5\sqrt{39}}{32}\div\frac{-7}{32}\\\\ tan(\alpha)=\frac{5\sqrt{39}}{32}\times\frac{32}{-7}\\\\ tan(\alpha)=-\frac{5\sqrt{39}}{7}\\\\\\ cot(\alpha)=-\frac{7}{5\sqrt{39}}\\\\ cot(\alpha)=-\frac{7\sqrt{39}}{5*39}\\\\ cot(\alpha)=-\frac{7\sqrt{39}}{195}\\\\
Mmm,
first α2 is between 45 and 67.5 degrees. so that is the first quadrant. All trig ratios are positive
so α must be between 90 and 135 degrees so that is the second quadrant. Only sine and cosec are positive all other ratios will be negative,
Now
\\cos \left(\frac{\alpha}{2}\right)=\frac{5}{8}\\\\ cos^2 \left(\frac{\alpha}{2}\right)=\frac{25}{64}\\\\ cos^2 \left(\frac{\alpha}{2}\right)+sin^2 \left(\frac{\alpha}{2}\right)=1}\\\\ \frac{25}{64}+sin^2 \left(\frac{\alpha}{2}\right)=1}\\\\ sin^2 \left(\frac{\alpha}{2}\right)=1-\frac{25}{64}\\\\ sin^2 \left(\frac{\alpha}{2}\right)=\frac{39}{64}\\\\ sin \left(\frac{\alpha}{2}\right)=\frac{\sqrt{39}}{8}\\\\\\
sin(α)=sin(α2+α2)sin(α)=2sinα2cosα2sin(α)=2∗√398∗58sin(α)=√394∗58sin(α)=5√3932Cosec(α)=325√39Cosec(α)=32√395∗39Cosec(α)=32√39195
cos(α)=cos(α2+α2)cos(α)=cos2(α2)−sin2(α2)cos(α)=2564−3964cos(α)=−1464cos(α)=−732sec(α)=−327
\\tan(\alpha)=sin(\alpha)}\div{cos(\alpha)}\\\\ tan(\alpha)=\frac{5\sqrt{39}}{32}\div\frac{-7}{32}\\\\ tan(\alpha)=\frac{5\sqrt{39}}{32}\times\frac{32}{-7}\\\\ tan(\alpha)=-\frac{5\sqrt{39}}{7}\\\\\\ cot(\alpha)=-\frac{7}{5\sqrt{39}}\\\\ cot(\alpha)=-\frac{7\sqrt{39}}{5*39}\\\\ cot(\alpha)=-\frac{7\sqrt{39}}{195}\\\\