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Find the sum.

sum_(k=1)^(38)(6k-105)=

Find the sum.\newlinek=138(6k105)= \sum_{k=1}^{38}(6 k-105)=

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Q. Find the sum.\newlinek=138(6k105)= \sum_{k=1}^{38}(6 k-105)=
  1. Find Sum of 6k6k: We need to find the sum of the series given by the expression (6k105)(6k-105) from k=1k=1 to 3838. We can separate the series into two parts: the sum of 6k6k and the sum of 105-105.
  2. Calculate Sum of 105-105: First, let's find the sum of the series 6k6k from k=1k=1 to 3838. This is an arithmetic series with a common difference of 66. The sum of an arithmetic series can be found using the formula S=n2×(a1+an)S = \frac{n}{2} \times (a_1 + a_n), where nn is the number of terms, a1a_1 is the first term, and ana_n is the last term.
  3. Find Total Sum: The first term a1a_1 when k=1k=1 is 6×1=66\times1 = 6, and the last term ana_n when k=38k=38 is 6×38=2286\times38 = 228. There are 3838 terms in total. Plugging these values into the formula gives us S=382×(6+228)S = \frac{38}{2} \times (6 + 228).
  4. Find Total Sum: The first term a1a_1 when k=1k=1 is 6×1=66\times1 = 6, and the last term ana_n when k=38k=38 is 6×38=2286\times38 = 228. There are 3838 terms in total. Plugging these values into the formula gives us S=382×(6+228)S = \frac{38}{2} \times (6 + 228).Calculating the sum S=19×(6+228)=19×234=4446S = 19 \times (6 + 228) = 19 \times 234 = 4446. This is the sum of the 6k6k part of the series.
  5. Find Total Sum: The first term a1a_1 when k=1k=1 is 6×1=66\times1 = 6, and the last term ana_n when k=38k=38 is 6×38=2286\times38 = 228. There are 3838 terms in total. Plugging these values into the formula gives us S=382×(6+228)S = \frac{38}{2} \times (6 + 228).Calculating the sum S=19×(6+228)=19×234=4446S = 19 \times (6 + 228) = 19 \times 234 = 4446. This is the sum of the 6k6k part of the series.Now, let's find the sum of the constant part of the series, which is k=1k=100 repeated 3838 times. The sum of a constant series is simply the constant times the number of terms. So, the sum is k=1k=122.
  6. Find Total Sum: The first term a1a_1 when k=1k=1 is 6×1=66\times1 = 6, and the last term ana_n when k=38k=38 is 6×38=2286\times38 = 228. There are 3838 terms in total. Plugging these values into the formula gives us S=382×(6+228)S = \frac{38}{2} \times (6 + 228).Calculating the sum S=19×(6+228)=19×234=4446S = 19 \times (6 + 228) = 19 \times 234 = 4446. This is the sum of the 6k6k part of the series.Now, let's find the sum of the constant part of the series, which is k=1k=100 repeated 3838 times. The sum of a constant series is simply the constant times the number of terms. So, the sum is k=1k=122.Calculating the sum of the constant part gives us k=1k=133.
  7. Find Total Sum: The first term a1a_1 when k=1k=1 is 6×1=66\times1 = 6, and the last term ana_n when k=38k=38 is 6×38=2286\times38 = 228. There are 3838 terms in total. Plugging these values into the formula gives us S=382×(6+228)S = \frac{38}{2} \times (6 + 228). Calculating the sum S=19×(6+228)=19×234=4446S = 19 \times (6 + 228) = 19 \times 234 = 4446. This is the sum of the 6k6k part of the series. Now, let's find the sum of the constant part of the series, which is k=1k=100 repeated 3838 times. The sum of a constant series is simply the constant times the number of terms. So, the sum is k=1k=122. Calculating the sum of the constant part gives us k=1k=133. Finally, we add the sum of the 6k6k part and the sum of the constant part to get the total sum of the series. So, the total sum is k=1k=155.

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