Tag: trigonometric identities

$\dfrac{\cos{20}^{o}+8\sin{70}^{o}\sin{50}^{o}\sin{10}^{o}}{{\sin}^{2}{80}^{0}}$ is equal to:

The value of expression $\dfrac { 2\left( \sin{ 1 }^{ o }+\sin{ 2 }^{ o }+\sin{ 3 }^{ o }+.....+\sin{ 89 }^{ o } \right)  }{ 2\left( \cos{ 1 }^{ o }+\cos{ 2 }^{ o}+......+\cos{ 44 }^{ o } \right) +1 }$ equals

${\cos}^{2}{73}^{o}+{\cos}^{2}{47}^{o}+\cos{73}^{o}\cos{47}^{o}=.$

$\dfrac { \cos{ 13 }^{ o }-\sin{ 13 }^{ o } }{ \cos{ 13 }^{ o }+\sin{ 13 }^{ o } } +\dfrac { 1 }{ \cot{ 148 }^{ o } }$ is equal to

The value of $\sqrt { 3 } tan{ 10 }^{ 0 }+\sqrt { 3 } tan{ 20 }^{ 0 }+tan{ 10 }^{ 0 }tan{ 20 }^{ 0 }$ is ___________.

If $sin(A-B)=\frac { 1 }{ 2 } ,cos(A+B)=\frac { 1 }{ 2 } ,{ 0 }^{ 0 }<A+B\le { 90 }^{ 0 }$ then A =

The value of $cos^2 10^o 15^o + cos^2 20^o +...... + cos^2 365^O$

$16 \cos^6 10^o - 24 \cos^4 10^o + 9 \cos^2 10^o$ is equal to

If $(1+\tan 1^{o})(1+\tan 2^{o})(1+\tan 3^{o})....(1+\tan 45^{o})=2^{n}$, then $n$ is equal to 

Values of : $sin{ 10 }^{ 0 }sin{ 50 }^{ 0 }sin{ 60 }^{ 0 }sin{ 70 }^{ 0 }$ is