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Question 12

For the equation,
[tex]\[ 2 \tan (\theta) + 2 = 0 \][/tex]

a. Solve for all degree solutions:
[tex]\[ \theta = \square + 360^\circ k \][/tex]

b. Solve for [tex]\(\theta\)[/tex] if [tex]\(0^\circ \leq \theta \ \textless \ 360^\circ\)[/tex]. Do not use a calculator.
[tex]\[ \theta = \square \][/tex]



Answer :

Let's solve the given equation [tex]\(2 \tan(\theta) + 2 = 0\)[/tex] step-by-step:

### Part (a): Solve for all degree solutions.

1. Rearrange the equation:
[tex]\[ 2 \tan(\theta) + 2 = 0 \][/tex]
Subtract 2 from both sides:
[tex]\[ 2 \tan(\theta) = -2 \][/tex]
Divide both sides by 2:
[tex]\[ \tan(\theta) = -1 \][/tex]

2. Find the general solution for [tex]\(\theta\)[/tex]:
The tangent function has a period of [tex]\(180^\circ\)[/tex]. Therefore, the general solution for [tex]\(\tan(\theta) = -1\)[/tex] can be written as:
[tex]\[ \theta = 135^\circ + 180^\circ k \][/tex]
where [tex]\(k\)[/tex] is any integer.

So, the general solution is:
[tex]\[ \boxed{\theta = 135^\circ + 180^\circ k} \][/tex]

### Part (b): Solve for [tex]\(\theta\)[/tex] in the interval [tex]\(0^\circ \leq \theta < 360^\circ\)[/tex].

1. Find specific solutions within the interval:
We need to find the values of [tex]\(\theta\)[/tex] that satisfy the equation [tex]\( \tan(\theta) = -1 \)[/tex] within the range [tex]\(0^\circ \leq \theta < 360^\circ\)[/tex].

2. Substitute [tex]\(k\)[/tex] into the general solution:
- For [tex]\(k = 0\)[/tex]:
[tex]\[ \theta = 135^\circ \][/tex]
- For [tex]\(k = 1\)[/tex]:
[tex]\[ \theta = 135^\circ + 180^\circ = 315^\circ \][/tex]
- For [tex]\(k = -1\)[/tex]:
[tex]\[ \theta = 135^\circ - 180^\circ = -45^\circ \][/tex]
Since [tex]\(-45^\circ\)[/tex] is not in the interval [tex]\(0^\circ \leq \theta < 360^\circ\)[/tex], we discard this value.

3. Verify all unique solutions within the given range:
We have:
[tex]\[ 135^\circ, 315^\circ \][/tex]

So, the solutions for [tex]\(\theta\)[/tex] in the interval [tex]\(0^\circ \leq \theta < 360^\circ\)[/tex] are:
[tex]\[ \boxed{135^\circ, 315^\circ} \][/tex]

To summarize:
(a) The general solution for the equation [tex]\(2 \tan(\theta) + 2 = 0\)[/tex] is:
[tex]\[ \theta = 135^\circ + 180^\circ k \][/tex]
(b) The specific solutions for [tex]\(\theta\)[/tex] within the range [tex]\(0^\circ \leq \theta < 360^\circ\)[/tex] are:
[tex]\[ 135^\circ, 315^\circ \][/tex]