Answer:
(0,7)
Step-by-step explanation:
For a set of ordered pairs to be a function, there needs to be "ONE" value of y for each unique x value.
Thus, we see that the 3 ordered pairs given have x values of 0, 2, and 3.
Now, we look in the answer choices and find which ones are 0, 2, or 3 in x-coordinate.
That would be only (0,7). Now the original set has x = 0 corresponding to y = 1
Is that true for (0,7)?? NO!
x = 0 will now correspond to "TWO" values of y.
THis will make this NOT A FUNCTION.
So, (0,7) is correct.
Find <span>tan<span>(<span><span>5π</span>12</span>)</span></span> and sin ((5pi)/12)
Answer: <span>±<span>(2±<span>√3</span>)</span>and±<span><span>√<span>2+<span>√3</span></span></span>2</span></span>
Explanation:
Call tan ((5pi/12) = t.
Use trig identity: <span><span>tan2</span>a=<span><span>2<span>tana</span></span><span>1−<span><span>tan2</span>a</span></span></span></span>
<span><span>tan<span>(<span><span>10π</span>12</span>)</span></span>=<span>tan<span>(<span><span>5π</span>6</span>)</span></span>=−<span>1<span>√3</span></span>=<span><span>2t</span><span>1−<span>t2</span></span></span></span>
<span><span>t2</span>−2<span>√3</span>t−1=0</span>
<span>D=<span>d2</span>=<span>b2</span>−4ac=12+4=16</span>--> <span>d=±4</span>
<span>t=<span>tan<span>(<span><span>5π</span>12</span>)</span></span>=<span><span>2<span>√3</span></span>2</span>±<span>42</span>=2±<span>√3</span></span>
Call <span><span>sin<span>(<span><span>5π</span>12</span>)</span></span>=<span>siny</span></span>
Use trig identity: <span><span>cos2</span>a=1−2<span><span>sin2</span>a</span></span>
<span><span>cos<span>(<span><span>10π</span>12</span>)</span></span>=<span>cos<span>(<span><span>5π</span>6</span>)</span></span>=<span><span>−<span>√3</span></span>2</span>=1−2<span><span>sin2</span>y</span></span>
<span><span><span>sin2</span>y</span>=<span><span>2+<span>√3</span></span>4</span></span>
<span><span>siny</span>=<span>sin<span>(<span><span>5π</span>12</span>)</span></span>=±<span><span><span>√<span>2+<span>√3</span></span></span>2</span></span></span>
Answer:
B
Step-by-step explanation:
The given equations satisfy the given conditions. There are 2 equations and 2 unknowns, so a certain solution can be found.
This can be solved using substitution,
Substituting eqn 2 to eqn 1:
2(2y – 10) + 3y =1240
Simplifying,
y = 180
x = 350
Answer:
105
Step-by-step explanation:
60/4= 15
15x7= 105
