Hello, math71321!
We have: .
. . . . . . . . . .
Then: .
Hence: .
Therefore: .
Square both sides: .
. . . . . . . . . . . .
which simplifies to: .
. . Therefore: .
im stuck on three questions and i really need to solve them
a) sec2x + 1/cosx = 0 x is between and equal to 0 and pie
b)cos^2x+2sinxcosx-sin^2x=0 x is between and equal to 0 and two pie
c)2tanx = secx x is between and equal to negative pie and two pie