The common difference, d, can be determined by subtracting the two consecutive values:
1 - 5 = -4
-3 - 1 = -4
-7 - -3 = -4
Then, using the equation:
an = a1+ d(n-1)
a_21 = 5 + (-4)(21 - 1)
a_21 = -75
The answer is letter D. I hope I was able to help you. Have a good day!
Answer:
f(-2) = 2
Step-by-step explanation:
Look at the graph and find -2 on the x-axis and see what the y-coordinate is on the line where x is -2. When you do this, you can see that where x is -2, y is 2.
So basically it wants the y-value :)
<h3>
Answer:</h3>
- left picture (bottom expression): -cot(x)
- right picture (top expression): tan(x)
<h3>
Step-by-step explanation:</h3>
A graphing calculator can show you a graph of each expression, which you can compare to the offered choices.
_____
You can make use of the relations ...
... sin(a)+sin(b) = 2sin((a+b)/2)cos((a-b)/2)
... cos(a)+cos(b) = 2cos((a+b)/2)cos((a-b)/2)
... cos(a)-cos(b) = -2sin((a+b)/2)sin((a-b)/2)
Then you have ...
and ...
Put a point at (0,4) then go down 1 and over 2 and there's another point. Connect the 2.
Answer:
Step-by-step explanation:
