If `Sinbeta` is geometric mean between `Sinalpha` and `cosalpha`, then `cos2beta=`

If sinbeta is geometric mean between sin alpha and cos alpha , then cos 2beta =

If sinbeta is the harmonic mean of sinalpha and cosalpha , and sintheta is the arithmetic mean of sinalpha" and "cosalpha , then which of the following is/are correct? 1. sqrt(2)sin(alpha+(pi)/(4))sinbeta=sin2alpha 2. sqrt(2)sintheta=cos(alpha-(pi)/(4)) Select the correct answer using the code given below:

If cos alpha + cosbeta=a, sinalpha + sinbeta=b and theta is the arithmetic mean between alpha and beta , then (sin2theta + cos 2theta) is equal to :

If cos alpha + cosbeta=a, sinalpha + sinbeta=b and theta is the arithmetic mean between alpha and beta , then (sin2theta + cos 2theta) is equal to :

If "cot"(alpha+beta)=0, then "sin"(alpha+2beta) can be (a) -sinalpha (b) sinbeta (c) cosalpha (d) cosbeta

If "cot"(alpha+beta)=0, then "sin"(alpha+2beta) can be (a) -sinalpha (b) sinbeta (c) cosalpha (d) cosbeta

The distance between the points (a cosalpha, a sinalpha) and (a cosbeta, a sinbeta) where a> 0

The distance between the points (a cosalpha, a sinalpha) and (a cosbeta, a sinbeta) where a> 0

The distance between the points (a cosalpha, a sinalpha) and (a cosbeta, a sinbeta) where a> 0

The distance between the points (a cosalpha, a sinalpha) and (a cosbeta, a sinbeta) where a> 0