Question 29
(GDR 1) Find all real numbers $\lambda$ such that the equation
$$\sin^4x-\cos^4x=\lambda(\tan^4x-\cot^4x)$$
(a) has no solution,
(b) has exactly one solution,
(c) has exactly two solutions,
(d) has more than two solutions (in the interval $(0,\pi/4)$).
$$\sin^4x-\cos^4x=\lambda(\tan^4x-\cot^4x)$$
(a) has no solution,
(b) has exactly one solution,
(c) has exactly two solutions,
(d) has more than two solutions (in the interval $(0,\pi/4)$).