`a=sec2^(@), b=sec2=>`

(sec2A+1)sec^2A=

sec^(2)A(1+sec2A)=2sec2A

Show that the coordinates of the orthocentre of DeltaABC is : ((x_1 a sec A + x_2 b sec B + x_3 c sec C)/(a sec A + b sec B + c sec A)), (y_1 a sec A + y_2 b sec B + y_3 c sec C)/(a sec A + b sec B + c sec C))

If m = a sec A + b tan A and n = a tan A + b sec A, then prove that : m^(2) - n^(2) = a^(2) - b^(2)

(1 + cot2 θ) (1 – cos θ) (1 + cos θ) = …………………. (a) tan2 θ – sec2 θ (b) sin2 θ – cos2 θ (c) sec2 θ – tan2 θ (d) cos2 θ – sin2 θ

(sec 2A+1 ) sec ^(2) A=

If sec A tan B+ tan A sec B=2 , sec A sec B +tan A tan B=k ,then k^(2) = (A) 2 (B) 5 (C) 4 (D) 1

(1+sec 2 theta)*sqrt(sec^(2) theta-1)= A) 2 sec theta B) sec 2 theta C) 2 tan theta D) tan 2 theta

1/sec2(theta) + 1/cosec2(theta) =