Answer:
Step-by-step explanation:
Given the explicit function as
f(n) = 15n+4
The first term of the sequence is at when n= 1
f(1) = 15(1)+4
f(1) = 19
a = 19
Common difference d = f(2)-f(1)
f(2) = 15(2)+4
f(2) = 34
d = 34-19
d = 15
Sum of nth term of an AP = n/2{2a+(n-1)d}
S20 = 20/2{2(19)+(20-1)15)
S20 = 10(38+19(15))
S20 = 10(38+285)
S20 = 10(323)
S20 = 3230.
Sum of the 20th term is 3230
For the explicit function
f(n) = 4n+15
f(1) = 4(1)+15
f(1) = 19
a = 19
Common difference d = f(2)-f(1)
f(2) = 4(2)+15
f(2) = 23
d = 23-19
d = 4
Sum of nth term of an AP = n/2{2a+(n-1)d}
S20 = 20/2{2(19)+(20-1)4)
S20 = 10(38+19(4))
S20 = 10(38+76)
S20 = 10(114)
S20 = 1140
Sum of the 20th terms is 1140
To find the solution
-4x>36
divide both sides by -4
(REMEMBER WHEN YOU DIVIDE BY A NEGATIVE, THE SIGN FLIPS OVER)
x < -36/4
simplified
x < -9
Hope this helps :)
Answer:
is the inequality to find the Domain of f(x)
Step-by-step explanation:
When we have a function where the variable "x" is inside a square root, we find its Domain by looking for all those values x for which the function is defined for the root, which means all the x-values that make the expression inside the root larger than or equal to zero, avoiding the values smaller for which the square root is not defined.
Therefore, in this case , for

we ask for the x-values that verify:

where we have isolated x on one side of the equal sign.
This would be the definition of the Domain of the function.
Answer: 39.8
Step-by-step explanation:
I just did it on edge 2021.