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#1 2017-07-30 16:45:12

Zeeshan 01
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Registered: 2016-07-22
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Different Questions

Question 1: If sinA=3/5 and cosA< zero ,then tan A= ???
Options(0.75,-0.66,-0.80,0.80)

Question 2: For any triangle if tangent of any internal angle=0 then the area of triangle is
Options(Zero,Infinity,Undefined,Not sure)

Question 3 : Which of the following about set of primes is not true
Options(Subset of Z,Finite,Odd except 1,Cannot divide each other)

I Think  it is odd except 1 this option is not true

Give ans or send me link of this topic


Malik

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#2 2017-07-31 20:58:49

zetafunc
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Re: Different Questions

For question 1,
must be negative (do you see why?). It seems to me that the answer should be
, which is not listed.

For question 2,
gives
or
. This corresponds to three collinear points.

For question 3, clearly all primes are integers, so they must be a subset of
, and by definition, none of them divide each other. For the "odd except 1" statement,
is a prime number, and
isn't a prime number either, so this statement can't be true. There are also infinitely many primes -- so it seems there are two false statements listed. Did you mean to write "odd except 2"?

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#3 2017-07-31 22:43:08

Zeeshan 01
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Re: Different Questions

Odd except First

Last edited by Zeeshan 01 (2017-08-01 00:16:42)


Malik

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#4 2017-07-31 22:44:21

Zeeshan 01
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Re: Different Questions

Q 1 how you bring ans of tan
Q 2 area of triangle??


Malik

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#5 2017-07-31 22:54:07

zetafunc
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Re: Different Questions

Zeeshan 01 wrote:

Odd except 1

In that case, there are two false statements.

Zeeshan 01 wrote:

Q 1 how you bring ans of tan

Use the fact that (3,4,5) is a Pythagorean triple.

Zeeshan 01 wrote:

Q 2 area of triangle??

What's the area of a triangle whose points all line on a straight line?

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#6 2017-08-01 00:18:21

zetafunc
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Re: Different Questions

Zeeshan 01 wrote:

Odd except First

OK, in that case, there is only one false statement: the finiteness claim.

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#7 2017-08-01 00:23:05

Zeeshan 01
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Re: Different Questions

Tan  A why Negative>>????


Malik

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#8 2017-08-01 00:24:25

Zeeshan 01
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Re: Different Questions

odd except first is only wrong???
what is except first mean??


Malik

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#9 2017-08-01 00:27:27

zetafunc
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Re: Different Questions

Zeeshan 01 wrote:

Tan  A why Negative>>????

Alternatively you can see this by drawing a triangle.

Zeeshan 01 wrote:

odd except first is only wrong???
what is except first mean??

That is a correct statement. It is claiming that all prime numbers, apart from the first prime number (that's
) are odd. The only statement which is not true is the 'finite' statement.

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#10 2017-08-01 00:29:04

Zeeshan 01
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Re: Different Questions

prime numbers is infinite


Malik

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#11 2017-08-01 00:30:28

zetafunc
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Re: Different Questions

Yes, exactly.

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#12 2017-08-01 00:30:42

Zeeshan 01
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Re: Different Questions

yes ans is 0.75 but negative is not in option


Malik

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#13 2017-08-01 00:35:47

zetafunc
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Re: Different Questions

If the answer were
, then that would imply that
(i.e. that it is positive).

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#14 2017-08-01 00:47:02

Zeeshan 01
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Re: Different Questions

Question 2


Malik

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#15 2017-08-01 00:57:51

zetafunc
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Re: Different Questions

Yes, what do you think the area of a triangle with all its points on a line could be?

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#16 2017-08-01 02:15:05

Zeeshan 01
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Re: Different Questions

0.8 is greater than zero 4/5


Malik

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#17 2017-08-01 02:23:47

zetafunc
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Re: Different Questions

Yes, which contradicts the assumption that

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#18 2017-08-01 16:23:01

Zeeshan 01
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Re: Different Questions

So what to do??


Malik

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#19 2017-08-02 00:53:18

Zeeshan 01
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Re: Different Questions

In this question


Malik

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#20 2017-08-02 00:54:57

zetafunc
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Re: Different Questions

I don't think any of the options listed are correct. The first option seems closest, though it has the wrong sign.

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#21 2017-08-02 00:57:34

Zeeshan 01
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Re: Different Questions

Ok area of triangle is half b×h


Malik

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#22 2017-08-02 00:58:18

zetafunc
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Re: Different Questions

So what is the area of the triangle in this case, do you think?

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#23 2017-08-02 00:59:14

Zeeshan 01
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Re: Different Questions

What is tangent of interior angle


Malik

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#24 2017-08-02 01:01:38

Zeeshan 01
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Re: Different Questions

Can u draw?


Malik

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#25 2017-08-02 01:05:36

zetafunc
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Re: Different Questions

The interior angle is just the angle between two sides.

By 'tangent', they mean
. That is, if
is the interior angle, they're asking you about
.

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