perpendiculars are drawn from the angles `A , Ba n dC` of an acute-angled triangle on the opposite sides, and produced to meet the circumscribing circle. If these produced parts are `alpha,beta,gamma` , respectively, then show that `a/alpha+b/beta+c/gamma=2(tanA+tanB+t a nC)dot`

Perpendiculars are drawn from the angles A, B and C of an acute-angled triangle onthe opposite sides, and produced to meet the circumscribing circle. If these produced parts are alpha., beta, gamma, respectively, then show that, then show that a/alpha+b/beta+c/gamma=2(tanA+tanB+tanC).

If the direction angles of a line are alpha, beta and gamma respectively, then cos 2 alpha + cos 2 beta + cos 2gamma is equal to

If a line makes angles alpha,beta,gamma with the axes respectively tehn cos2alpha+cos2beta+cos2gamma= -2 b. -1 c. 1 d. 2

PQ and QR are two focal chords of an ellipse and the eccentric angles of P,Q,R are 2alpha, 2beta, 2 gamma , respectively then tan beta gamma is equal to

If a vector makes angle alpha,beta,gamma with OX, OY and OZ respectively, then write the value of sin^2alpha+sin^2beta+sin^2gammadot

If a vector makes angles alpha,beta,gamma. with . OX ,O Ya n dO Z respectively, prove that sin^2alpha+sin^2beta+sin^2gamma=2.

If a line makes angles alpha, beta, gamma with the axes then cos2alpha +cos2beta+cos2gamma = (A) -2 (B) -1 (C) 1 (D) 2

If vec(A) makes an angle alpha, beta and gamma from x,y and z axis respectively then sin^(2)alpha+sin^(2) beta+sin^(2) gamma=

If the distances of the vertices of a triangle =ABC from the points of contacts of the incercle with sides are alpha,betaa n dgamma then prove that r^2=(alphabetagamma)/(alpha+beta+gamma)

Area of the triangle formed by the tangents at the point on the ellipse x^2/a^2+y^2/b^2=1 whose eccentric angles are alpha,beta,gamma is