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3 years ago

10

Joe's cell phone plan costs him $21 per month plus $3 for every 1 GB of data downloaded. What is the limit to the number of Gb's

he can download to stay within his monthly budget of $30?

1 answer:

DIA [1.3K]3 years ago

7 0

3 GB every month..... 21+3=24+3=27+3=30....so 3 GB

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Look at the triangles shown below.

Sophie [7]

Answer:

Variant c

Step-by-step explanation:

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c=6

You can apply phyphagor

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2 years ago

Help me with trigonometry

poizon [28]

Answer:

See below

Step-by-step explanation:

It has something to do with the<em> </em><u><em>Weierstrass substitution</em></u>, where we have

$\int\, f(\sin(x), \cos(x))dx = \int\, \dfrac{2}{1+t^2}f\left(\dfrac{2t}{1+t^2}, \dfrac{1-t^2}{1+t^2} \right)dt$

First, consider the double angle formula for tangent:

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$\tan\left(2 \cdot\dfrac{x}{2}\right)= \dfrac{2\tan(x/2)}{1-\tan^2(x/2)} = \tan(x)=\dfrac{2t}{1-t^2}$

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Recall

$\sin \arctan t = \dfrac{t}{\sqrt{1 + t^2}} \text{ and } \cos \arctan t = \dfrac{1}{\sqrt{1 + t^2}}$

Thus,

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Similarly for cosine, consider the double angle identity

Thus,

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======================================================

$5\cos(x) =12\sin(x) +3, x \in [0, 2\pi ]$

Solving

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$\implies \dfrac{5-5t^2}{1+t^2}= \dfrac{24t}{1+t^2}+3 \implies \dfrac{5-5t^2 -24t}{1+t^2}= 3$

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Just note that

$\tan\left(\dfrac{x}{2}\right) = \dfrac{3\pm 8\sqrt{10}}{-2}$

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luda_lava [24]

Answer:the nth term of the sequence, Tn= -3n +12

Step-by-step explanation:

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Tn= a+ (n-1) d

where a= first term

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The first term, a= 9

and common difference, d = -3

using our formulae

Tn= a+ (n-1) d

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Answer:

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Step-by-step explanation:

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Step-by-step explanation:

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