Graph x<2, need help on this one please.

Mathematics

1 answer:

pogonyaev3 years ago

5 0

Okay. So, the line shaded would have to be left to 2, because it's less than 2. In that case, A and C are eliminated, because they shade to the right, not left. B and D do this, but wait. The dotted line has to represent the less than, because the one that's fully filled in would mean less than or equal to. B would make sense, because the line is dotted and that makes an inequality symbol of less than, not less than or equal to. The answer is B.

Note: When the sign is < or >, the line on the graph is dotted. If the sign is <= or >=, then the line on the graph is solid.

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An Interesting Equation of Order n: xy" - (x + n)y' + ny = 0: u(x) = e^x. (a) Prove that the given solution is indeed a solution

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Solution:

The given differential equation is

x y" -(x+n)y'+ny=0------------(1)

Let, y'=t

y"=t'

$\frac{dy}{dx}=t\\\\y=t x$

Substituting the value of , y', y'' and y in equation (1)

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→ x t' = x t+ n t- nt x

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