trigonometry

Related Questions

• If $x=y\cos \frac{2\pi }{3}=z\cos \frac{4\pi }{3}$, then $xy+yz+zx=$

  ---

• The circum-radius of the triangle whose sides are 13, 12 and 5 is

  ---

• The value of $\tan {{20}^{o}}+2\tan {{50}^{o}}-\tan {{70}^{o}}$is equal to

  ---

• In a triangle $PQR$ , $\angle R=\frac{\pi }{2}.$ If $\tan \left( \frac{P}{2} \right)$ and $\tan \left( \frac{Q}{2} \right)$ are the roots of the equation $a{{x}^{2}}+bx+c=0(a\ne 0).$ then

  ---

• If $0\le x\le \pi $and ${{81}^{{{\sin }^{2}}x}}+{{81}^{{{\cos }^{2}}x}}=30$, then x =

  ---