The lines must be parallel to 3x-y = 5, . So their slope must be .
Let our line be , m is the slope and C is a constant. As it'll become
At the tangent point, the line must satisfy .
So the line passes the points (-1,f(-1)) and (1,f(1)).
The line is
And it makes for (-1,1)
and for (-1,1)
The lines are then
bu arada, türk müsün? =)