Question

Which of the following are not trigonometric identities? Check all that apply. (attached below)

Answer 1

@amistre64

Answer 2

@jim_thompson5910

Answer 3

all trig identites stem from the basic sin cos one .. what is the basic sin cos one?

Answer 4

the correct identity is \[\sin^2(x) + \cos^2(x) = 1\]

Answer 5

or we can have someone else determine it for you ...

now we can divide by sin^2 or cos^2 and form the others ...

Answer 6

fo simplicity i juat do

s^2 + c^2 = 1 and work it from there

Answer 7

oh ok so sin and cos are trigonometric identities and the others are not

Answer 8

no, this is the starting point, all the other trig identites will stem from this one.

Answer 9

what happens when we divide by s^2?

Answer 10

when we divide by sin^2 im not exactly sure?

Answer 11

divide it thru, show me the results you get

Answer 12

divide it thru?

Answer 13

yeah, divide both sides by s^2 ... its a very basic mathematical process to do ... you hit the / key and then place next to it the s^2

Answer 14

and it might help to knock off the obvious one

s^2 + c^2 = 1 is not going to work out to be s^2 - c^2 = 1 is it?

Answer 15

no

Answer 16

then lets pick D right off the bat lol, the rest we can either confirm or reject

Answer 17

s^2 + c^2 = 1 ; divide both sides by s^2 (why?)

s^2/s^2 + c^2/s^2 = 1/s^2 , simplify

1 + (c/s)^2 = (1/s)^2 what is another name for c/s and 1/s?

Answer 18

do it again but divide by c^2 instead .... you get another trig identity

Answer 19

I looks like C. 1+cot^2 x = csc^2 x is a trigonometric identity

Answer 20

http://www.sosmath.com/trig/Trig5/trig5/trig5.html

Answer 21

it is yes

Answer 22

so far I think the others are not but I am still looking

Answer 23

A and B are at odds with each other, dividing by c^2 should clear it up

Answer 24

ok so far I see that d is not c is and it looks like a and b are not to

Answer 25

A and B are at odds with each other, one is right the other is wrong

lets see how it works

s^2/c^2 + c^2/c^2 = 1/c^2

(s/c)^2 + 1 = (1/c)^2

what can we conclude from this?

Answer 26

since we have no (1/s)^2 one of them is clearly off

tan^2 + 1 = sec^2 , does this look like it can match one of them?

Answer 27

@amistre64 we can match b

Answer 28

yes, b is a match

sec^2 - tan^2 = 1 is a fair rewrite of our identity

Answer 29

@amistre64 so b and d would be the answers to this problem. Thank you for your help and time :)

Answer 30

um, we are looking for the ones that are NOT trig identies

D fails from the start, but B is good .... and C is good

that means A and D are what they are looking for

Answer 31

oh im sorrylol a and d because b and c are trigonometric identities thank you

Answer 32

your welcome :)