Find all angles, [tex]0^{\circ} \leq \theta \ \textless \ 360^{\circ}[/tex], that satisfy the equation below, to the nearest tenth of a degree.

[tex]\tan ^2 \theta - 5 \tan \theta = 0[/tex]



Answer :

To find all angles [tex]\( 0^{\circ} \leq \theta < 360^{\circ} \)[/tex] that satisfy the equation [tex]\( \tan^2 \theta - 5 \tan \theta = 0 \)[/tex], we can follow these steps:

1. Rewriting the equation as a quadratic equation:
[tex]\[ \tan^2 \theta - 5 \tan \theta = 0 \][/tex]
This equation can be factored to:
[tex]\[ \tan \theta (\tan \theta - 5) = 0 \][/tex]

2. Solving for [tex]\( \tan \theta \)[/tex]:
[tex]\[ \tan \theta = 0 \quad \text{or} \quad \tan \theta - 5 = 0 \][/tex]
This results in:
[tex]\[ \tan \theta = 0 \quad \text{or} \quad \tan \theta = 5 \][/tex]

3. Finding angles for [tex]\(\tan \theta = 0\)[/tex]:
- The tangent function is zero at angles [tex]\( \theta = 0^\circ \)[/tex] and [tex]\( \theta = 180^\circ \)[/tex] within the given range [tex]\( 0^\circ \leq \theta < 360^\circ \)[/tex].

4. Finding angles for [tex]\(\tan \theta = 5\)[/tex]:
- We need to find [tex]\( \theta \)[/tex] such that the tangent of [tex]\( \theta \)[/tex] is 5. Such angles occur at:
[tex]\[ \theta = \arctan(5) \][/tex]
- Calculating the principal value, we have:
[tex]\[ \theta \approx 78.7^\circ \][/tex]
- The tangent function repeats every [tex]\( 180^\circ \)[/tex] because it is periodic with a period of [tex]\( 180^\circ \)[/tex]. Therefore, the other angle within the range is:
[tex]\[ \theta = 78.7^\circ + 180^\circ = 258.7^\circ \][/tex]

5. Combining all valid angles:
- For [tex]\( \tan \theta = 0 \)[/tex], the angles are [tex]\( 0^\circ \)[/tex] and [tex]\( 180^\circ \)[/tex].
- For [tex]\( \tan \theta = 5 \)[/tex], the angles are [tex]\( 78.7^\circ \)[/tex] and [tex]\( 258.7^\circ \)[/tex].

Therefore, the angles [tex]\( \theta \)[/tex] that satisfy the equation [tex]\( \tan^2 \theta - 5 \tan \theta = 0 \)[/tex] within the range [tex]\( 0^\circ \leq \theta < 360^\circ \)[/tex] are:

[tex]\[ \boxed{0.0^\circ, 180.0^\circ, 78.7^\circ, 258.7^\circ} \][/tex]