Answer:
n = 9
Step-by-step explanation:
20 + 18 + ... + 6 + 4
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a = 20 ; d = -2 ; n = ?
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4 = 20 + (n-1)(-2)
-16 = (n-1)(-2)
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n-1 = 8
n = 9
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S(9) = (9/2)(20+4)
S(9) = 4.5*24
S(9) = 108
Answer:
f(3) = 3
Step-by-step explanation:
f(x) = 2x^2 – 5x
Let x = 3
f(3) = 2(3)^2 - 5(3)
= 2*9 -15
= 18-15
=3
The length of CD is 7-3=4.
Therefore, if we dilate by a scale factor of 3, the length is 4(3) = 12
(xy)' + (2x)' + (3x^2)' = (4)'
y + xy' + 2 + 6x = 0
xy' = -y -2 -6x
y' = [-y -2 -6x] / x
Now solve y from the original equation and substitue
xy + 2x + 3x^2 = 4 => y = [-2x - 3x^2 + 4] / x
y' = [(-2x - 3x^2 +4) / x - 2 - 6x ] / x
y' = [-2x - 3x^2 + 4 -2x -6x^2 ] x^2 = [ -4x - 9x^2 + 4] / x^2 =
= [-9x^2 - 4x + 4] / x^2