Given 3 + 7 + 11 + 15 + ... find S20

Mathematics

1 answer:

nasty-shy [4]2 years ago

6 0

=4n - 1
Since the sequence is add 4 and 3-4 = -1

20 x 4n = 80-1 = 79

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The value of -9(square root) is not-3 because

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Answer:

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Step-by-step explanation:

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2 years ago

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Evaluate \dfrac{3}{2}+(-k)+(-2)

Dimas [21]

As I understand, we need to evaluate the given rational expression, we will get that the evaluated expression is equal to - 1/10

<h3>Evaluating expressions:</h3>

Evaluating an expression just means that we need to replace the variable in the expression for a given value, here we have the expression:

$\frac{3}{2} + (-k) + (-2)$

And we want to evaluate it in:

$k = -\frac{2}{5}$

So we just need to replace k by that value in the above expression, we will get:

$\frac{3}{2} + (-(-\frac{2}{5} )) + (-2)$

Now we can just solve this:

$\frac{3}{2} + (-(-\frac{2}{5} )) + (-2)\\\\\frac{3}{2} + \frac{2}{5} + (-2)\\\\\frac{15}{10} + \frac{4}{10} + (-2) = \frac{19}{10} - \frac{20}{10}= -\frac{1}{10}$