Physics help

Rainy2Day · #1 $Old$ 08-28-2008, 05:31 PM

Hello there,

I dont even know where to start with this problem

so I hope someone here can spare some time and help me

1) Using your calculator verify that sin 0 divided by Cos 0 is equal to tan 0 for angle 0. Try 30 degrees and prove that this result is true in general by using the definitions for sin - and cos 0 and tan 0.

Thanks in advance

skeeter · #2 $Old$ 08-28-2008, 06:00 PM

you can do the calculator verification, right?

definitions ...

$\cos{\theta} = \frac{x}{r}$
$\sin{\theta} = \frac{y}{r}$
$\tan{\theta} = \frac{y}{x}$

now, use the above definitions to show that
$\tan{\theta} = \frac{\sin{\theta}}{\cos{\theta}}$

Rainy2Day · #3 $Old$ 08-28-2008, 06:19 PM

Umm how do you exactly do a calculator verification?

skeeter · #4 $Old$ 08-28-2008, 06:31 PM

what kind of calculator do you have?

Rainy2Day · #5 $Old$ 08-28-2008, 06:44 PM

I got a ti-84 Plus not really sure how to use it though

skeeter · #6 $Old$ 08-28-2008, 07:07 PM

1. press the [MODE] button, move the dark blinking cursor on top of the word degree and press [ENTER].

2. go back to the home screen by pressing [2nd] [MODE].

3. enter the expression sin(0)/cos(0) then [ENTER] ... the calculator will return the value 0.

4. enter tan(0) and [ENTER] ... the calculator will return the same value 0.

5. Do the same operations with other angles ... 30 degrees, 52 degrees, whatever ... you'll see that the sin/cos calculation yield the same value as the tangent calculation. As such, you've verified that sin(x)/cos(x) = tan(x) with the calculator.

Rainy2Day · #7 $Old$ 08-28-2008, 07:15 PM

Thank you for your help

It is much appreciated