fundimental identies - Math Help Forum

$Math Help Forum$

$Go Back$		Math Help Forum > Pre-University Math Help > Trigonometry
$Reload this Page$ fundimental identies

Download MHF Flyer

Mark Forums Read

$Reply$

#1

$Old$ November 2nd, 2009, 08:08 PM

wenatchee $wenatchee is offline$

Newbie

Join Date: Nov 2009

Posts: 14

Country:

United States

Thanks: 13

Thanked 1 Time in 1 Post

$wenatchee is on a distinguished road$

$Default$ fundimental identies

use the fundimental identies to find the value of the trigonomic function.
sin 0, if cos 0 = 2/3 and 0 is in quadrant IV

-3/2
(3 square root 7)/7
5/4
-( square root 5)/3

$Reply With Quote$

Advertisement

#2

$Old$ November 2nd, 2009, 08:12 PM

Prove It $Prove It is offline$

MHF Contributor

Join Date: Aug 2008

Posts: 2,741

Country:

Australia

Thanks: 69

Thanked 1,085 Times in 1,017 Posts

$Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$

$Default$

Quote:

Originally Posted by wenatchee $View Post$

use the fundimental identies to find the value of the trigonomic function.
sin 0, if cos 0 = 2/3 and 0 is in quadrant IV

-3/2
(3 square root 7)/7
5/4
-( square root 5)/3

Is your 0 supposed to represent $\theta$ ?

Make use of the Pythagorean Identity:

$\cos^2{\theta} + \sin^2{\theta} = 1$

$\left(\frac{2}{3}\right)^2 + \sin^2{\theta} = 1$

$\frac{4}{9} + \sin^2{\theta} = 1$

$\sin^2{\theta} = \frac{5}{9}$

$\sin{\theta} = \pm \frac{\sqrt{5}}{3}$ .

Since $\theta$ is in Quadrant 4, we know $\sin{\theta}< 0$ .

So $\sin{\theta} = -\frac{\sqrt{5}}{3}$ .

__________________

Two things are infinite - The Universe and Human Stupidity. Though I'm not too sure about the universe...

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
and
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

$Reply With Quote$

The following users thank Prove It for this useful post:
wenatchee
$Donate to MHF$

#3

$Old$ November 2nd, 2009, 08:13 PM

$VonNemo19's Avatar$

VonNemo19 $VonNemo19 is offline$

No one in Particular

Join Date: Apr 2009

Location: Detroit, MI

Posts: 1,725

Country:

United States

Thanks: 461

Thanked 534 Times in 500 Posts

$VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$

$Default$

Quote:

Originally Posted by wenatchee $View Post$

use the fundimental identies to find the value of the trigonomic function.
sin 0, if cos 0 = 2/3 and 0 is in quadrant IV

-3/2
(3 square root 7)/7
5/4
-( square root 5)/3

I take it that by "0", you mean $\theta$ .

So...

$\sin\theta=\sqrt{1-\cos^2\theta}$

Can you see what needs to be done?

__________________

"Then thou carriedst thine ashes into the mountains:

wilt thou now carry thy fire into the valleys?"

Thus Spake Zarathustra

Friedrich Nietzsche

If you would like to know how the quadratic formula was derived, visit my post entitled:

Deriving the Quadratic Formula.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

$Reply With Quote$

The following users thank VonNemo19 for this useful post:
wenatchee
$Donate to MHF$

#4

$Old$ November 2nd, 2009, 08:14 PM

Prove It $Prove It is offline$

MHF Contributor

Join Date: Aug 2008

Posts: 2,741

Country:

Australia

Thanks: 69

Thanked 1,085 Times in 1,017 Posts

$Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$

$Default$

Quote:

Originally Posted by VonNemo19 $View Post$

I take it that by "0", you mean $\theta$ .

So...

$\sin\theta=\sqrt{1-\cos^2\theta}$

Can you see what needs to be done?

Beat ya

__________________

Two things are infinite - The Universe and Human Stupidity. Though I'm not too sure about the universe...

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
and
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

$Reply With Quote$

The following users thank Prove It for this useful post:
wenatchee
$Donate to MHF$

#5

$Old$ November 2nd, 2009, 08:20 PM

$VonNemo19's Avatar$

VonNemo19 $VonNemo19 is offline$

No one in Particular

Join Date: Apr 2009

Location: Detroit, MI

Posts: 1,725

Country:

United States

Thanks: 461

Thanked 534 Times in 500 Posts

$VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$

$Default$

Quote:

Originally Posted by Prove It $View Post$

Beat ya

You did indeed, you scoundrel! Until we meet again, Proveit!

__________________

"Then thou carriedst thine ashes into the mountains:

wilt thou now carry thy fire into the valleys?"

Thus Spake Zarathustra

Friedrich Nietzsche

If you would like to know how the quadratic formula was derived, visit my post entitled:

Deriving the Quadratic Formula.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

$Reply With Quote$

The following users thank VonNemo19 for this useful post:
wenatchee
$Donate to MHF$

#6

$Old$ November 2nd, 2009, 08:22 PM

wenatchee $wenatchee is offline$

Newbie

Join Date: Nov 2009

Posts: 14

Country:

United States

Thanks: 13

Thanked 1 Time in 1 Post

$wenatchee is on a distinguished road$

$Default$ slowly

Thanks I left my book and calculator at school and missed this whole section due to swine flu.

$Reply With Quote$

#7

$Old$ November 2nd, 2009, 08:24 PM

$VonNemo19's Avatar$

VonNemo19 $VonNemo19 is offline$

No one in Particular

Join Date: Apr 2009

Location: Detroit, MI

Posts: 1,725

Country:

United States

Thanks: 461

Thanked 534 Times in 500 Posts

$VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$ $VonNemo19 is a name known to all$

$Default$

Quote:

Originally Posted by wenatchee $View Post$

Thanks I left my book and calculator at school and missed this whole section due to swine flu.

Where you from? In the US, I mean.

__________________

"Then thou carriedst thine ashes into the mountains:

wilt thou now carry thy fire into the valleys?"

Thus Spake Zarathustra

Friedrich Nietzsche

If you would like to know how the quadratic formula was derived, visit my post entitled:

Deriving the Quadratic Formula.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

$Reply With Quote$

The following users thank VonNemo19 for this useful post:
wenatchee
$Donate to MHF$

#8

$Old$ November 2nd, 2009, 08:26 PM

wenatchee $wenatchee is offline$

Newbie

Join Date: Nov 2009

Posts: 14

Country:

United States

Thanks: 13

Thanked 1 Time in 1 Post

$wenatchee is on a distinguished road$

$Default$

how do you get all the math symbols

$Reply With Quote$

#9

$Old$ November 2nd, 2009, 08:26 PM

wenatchee $wenatchee is offline$

Newbie

Join Date: Nov 2009

Posts: 14

Country:

United States

Thanks: 13

Thanked 1 Time in 1 Post

$wenatchee is on a distinguished road$

$Default$

malaga washington

$Reply With Quote$

The following users thank wenatchee for this useful post:
VonNemo19
$Donate to MHF$

#10

$Old$ November 2nd, 2009, 08:34 PM

Prove It $Prove It is offline$

MHF Contributor

Join Date: Aug 2008

Posts: 2,741

Country:

Australia

Thanks: 69

Thanked 1,085 Times in 1,017 Posts

$Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$

$Default$

You get the math symbols using LaTeX.

Go to the LaTeX help sub-forum on this site, and read through the tutorials.

__________________

Two things are infinite - The Universe and Human Stupidity. Though I'm not too sure about the universe...

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
and
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

$Reply With Quote$

The following users thank Prove It for this useful post:
wenatchee
$Donate to MHF$

#11

$Old$ November 2nd, 2009, 08:47 PM

wenatchee $wenatchee is offline$

Newbie

Join Date: Nov 2009

Posts: 14

Country:

United States

Thanks: 13

Thanked 1 Time in 1 Post

$wenatchee is on a distinguished road$

$Default$

Where in Austrailia are you from? I used to live in Sydney for about 6 months.

$Reply With Quote$

#12

$Old$ November 3rd, 2009, 01:47 PM

Prove It $Prove It is offline$

MHF Contributor

Join Date: Aug 2008

Posts: 2,741

Country:

Australia

Thanks: 69

Thanked 1,085 Times in 1,017 Posts

$Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$ $Prove It has much to be proud of$

$Default$

Melbourne, but I am currently living in Mildura.

__________________

Two things are infinite - The Universe and Human Stupidity. Though I'm not too sure about the universe...

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
and
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

$Reply With Quote$

$Reply$

« Double-Angle Formulas | Top | Sum and Difference Formulas »

Thread Tools
$Show Printable Version$ Show Printable Version $Email this Page$ Email this Page
Display Modes
$Linear Mode$ Linear Mode $Hybrid Mode$ Switch to Hybrid Mode $Threaded Mode$ Switch to Threaded Mode

Posting Rules
You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off Trackbacks are Off Pingbacks are Off Refbacks are Off

Forum Jump

All times are GMT -7. The time now is 05:59 AM.

your link here Sponsors

rv solar, e-learning,

Math Help Forum is a community of maths forums with an emphasis on maths help in all levels of mathematics.
Register to post your math questions or just hang out and try some of our math games or visit the arcade.