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2 years ago

Which of the following are identities?

Mathematics

1 answer:

frosja888 [35]2 years ago

4 0

Answer:

A and D.

Step-by-step explanation:

(sin(x-y))/(cosxcosy)

(sinxcosy - cosxsiny) / cosxcosy

= sinx / cosx - siny/cosy

= tanx - tany.

So A is an identity.

B. (sin(x+y))/(sinxsiny)

= sinx cosy + cosx siny / sinxsiny

= cosy/siny + cosx/sinx

= 1/tany + 1/tanx which is not identical with 1-tanxtany.

C. tan ( x - pi/4) = ( tan x - 1) / (1 + tanx) : - not identical to tanx - 1.

D. cos( x + (pi/6) = cosxcos(pi/6) - sinxsin(pi/6)

= 0.866cosx - 0.5sinx

- sin(x - (pi/3) = -(sinxcos(pi/3) - cosxsin(p/3))

= - (0.5sinx - 0.866cosx0

= 0.866cos x - 0.5sinx.

which are identical.

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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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3 years ago

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3 years ago

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2 years ago

Silvio is an air-traffic controller who must calculate the altitude of an incoming plane. He sees the plane at an angle of eleva

Mrac [35]

Since the problem is not telling us the height of Silvio, we are going to assume it is not relevant for our calculations.
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We can conclude that we should use the trig function tangent to model this situation; also, we can conclude that the equation that describes this situation is $h=3tan(40)$ .

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3 years ago