If `1+ cos alpha + cos^2 alpha +.... = 2 - sqrt2`, then `alpha (0 < alpha < pi)`

If 1+cos alpha+cos^(2)alpha+...=2-sqrt(2), then alpha(0

If 1 + cos alpha + cos^(2) alpha + ….oo= 2- sqrt2 then find the value of alpha. (0 lt alpha lt pi)

If 1+cos alpha+cos ^(2) alpha+….=2-sqrt(2) , thet alpha(0 lt alpha lt pi) is

if 1+cos alpha+cos^(2)alpha+..........+oo=2-sqrt(2) where alpha varepsilon(0,pi) then find the value of alpha

If 0 < alpha < pi/6 and sin alpha + cos alpha =sqrt(7 )/2, then tan alpha/2 is equal to

If 0 lt alpha lt (pi)/(2) and sin alpha + cos alpha = sqrt2, then the value of cos 3 alpha is-

If sin alpha + cos alpha = sqrt2 cos alpha,"show that",tan 2 alpha = 1

If cos^(2)theta-sin^(2)theta=tan^(2)alpha, "then" : sqrt2 * cos theta * cos alpha=.... A) sin theta * sin alpha B)1 C) tan^(2)theta D)none of these

If A = cos ^(2) alpha + cos ^2(alpha + beta)- 2 cos alpha cos beta cos (alpha + beta), then