The sum of the first 20 terms of an arithmetic sequence with the 18th term of 8.1 and a common difference of 0.25 is 124.5
Given,
18th term of an arithmetic sequence = 8.1
Common difference = d = 0.25.
<h3>What is an arithmetic sequence?</h3>
The sequence in which the difference between the consecutive term is constant.
The nth term is denoted by:
a_n = a + ( n - 1 ) d
The sum of an arithmetic sequence:
S_n = n/2 [ 2a + ( n - 1 ) d ]
Find the 18th term of the sequence.
18th term = 8.1
d = 0.25
8.1 = a + ( 18 - 1 ) 0.25
8.1 = a + 17 x 0.25
8.1 = a + 4.25
a = 8.1 - 4.25
a = 3.85
Find the sum of 20 terms.
S_20 = 20 / 2 [ 2 x 3.85 + ( 20 - 1 ) 0.25 ]
= 10 [ 7.7 + 19 x 0.25 ]
= 10 [ 7.7 + 4.75 ]
= 10 x 12.45
= 124.5
Thus the sum of the first 20 terms of an arithmetic sequence with the 18th term of 8.1 and a common difference of 0.25 is 124.5
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Answer:
63°
Step-by-step explanation:
Angle <2 and the angle with measure of 63 are alternate exterior angles and has same measurement.
This is an incomplete question, here is a complete question and image is also attached below.
How much longer is the hypotenuse of the triangle than its shorter leg?
a. 2 ft
b. 4 ft
c. 8 ft
d. 10 ft
Answer : The correct option is, (b) 4 ft
Step-by-step explanation:
Using Pythagoras theorem in ΔACB :


Given:
Side AC = 6 ft
Side BC = 8 ft
Now put all the values in the above expression, we get the value of side AB.



Now we have to calculate the how much longer is the hypotenuse of the triangle than its shorter leg.
Difference = Side AB - Side AC
Difference = 10 ft - 6 ft
Difference = 4 ft
Therefore, the 4 ft longer is the hypotenuse of the triangle than its shorter leg.
Answer:
(a) f'(1)=-4
(b) y+4x-4=0
Step-by-step explanation:
<u>Tangent Line of a Function</u>
Given f(x) a real differentiable function in x=a, the slope of the tangent line of the function in x=a is given by f'(x=a). Where f' is the first derivative of f.
We are given

The derivative is

(a) The slope of the tangent line at (1,0) is


(b) The equation of the tangent line can be found with the general formula of the line:

Where m is the slope and the point (xo,yo) belongs to the line. We have m=-4, xo=1, yo=0, thus

Or, equivalently
