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3 years ago

Which of the following are identities?

Mathematics

1 answer:

frosja888 [35]3 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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3 years ago

What is -2.4x +3.8x-x

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3 years ago

Find the slope of a line that passes through the

Doss [256]

Given that,

Point 1 = (-6,9)

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To find,

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Solution,

We have,

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2 years ago

The Seniors at three high schools were surveyed about their plans after graduation. The following table shows the responses, cla

saw5 [17]

Answer:

E. 396/538

Step-by-step explanation:

The probability that the senior selected will not be from High School B given that the senior did not answer colege:

First, what's the probability of not having answered college? This will be out denominator.

P(not choosing college) = 244 + 106 + 188 = 538

Next, what's the probability that a senior in that category is not from HS B? Well, add the probabilities that the senior is in HS A or C:

P(senior is in HS A or C and answered not college) = 49 + 99 + 63 + 83 + 31 + 71 = 396

Our answer is E. 396/538.

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3 years ago

Please help me 10 points

Nonamiya [84]

Answer:

see below

Step-by-step explanation:

The following definitions apply:

if p, then q . . . . conditional statement

if q, then p . . . . converse

if ~p then ~q . . . inverse

if ~q then ~p . . . contrapositive

You have ...

p = "it is October 31"

q = "it is Halloween"

(a) The converse is ...

If it is Halloween, then it is October 31.

(b) The inverse is ...

If it is not October 31, then it is not Halloween.

(c) The contrapositive is ...

if it is not Halloween, then it is not October 31.

4 0

2 years ago