Hi, please help me with this question. what is 45+46+47+ ... +53+54?
2 answers:
9514 1404 393
Answer:
495
Step-by-step explanation:
There are several ways to figure this:
1) Multiply the average value by the number of numbers. The average number in an arithmetic sequence is the average of the first and last numbers in the sequence.
average = (54+45)/2 = 49.5
number of numbers = 54 -45 +1 = 10
Total = 49.5 · 10 = 495
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2) Add the numbers pairwise. It works best to work toward the middle from the ends:
45 +54 = 99
46 +53 = 99
47 +52 = 99
48 +51 = 99
49 +50 = 99
Total = 5 · 99 = 495
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3) Subtract the sum of numbers to 44 from the sum of numbers to 54.
The sum of numbers 1 to n is (n)(n+1)/2.
(54)(55)/2 -(44)(45)/2 = (27)(55) -(22)(45) = 1485 -990 = 495
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4) Use a spreadsheet or calculator to add them. (see attached)
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Answer:
Step-by-step explanation:
Finding the domain:
The domain of a function is the set of possible input values for which the function is real and defined.
Given the function
The function has no undefined points nor domain constraints. Hence, the domain is
i.e.
Finding the range:
The range of a function is the set of possible output values (dependent variable y values) for which a function is defined.
The range of polynomials with odd degree is all the real numbers.
Hence, the domain is
i.e.