# Would a trig expert please help?

#

**1**la vache fantôme

Thread Starter

Join Date: Aug 2004

Location: NH

Posts: 6,266

Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 1 Post(s)

**Would a trig expert please help?**

Im trying to figure out these stupid inverse functions in trig. I know Soh Cah Toa. And im good with that but now its stuff where instead of being given the value of your angle (theta) and the value of one length and you find the rest. Its 2 lengths and you find the angle.

So heres the problem:

A cable 4m long is attached to a pole. This cable is staked to the ground 1.75m from the base of the pole. Find the angle that the cable makes with the ground.

I used the bottom left angle as my theta. I think its the Sin -1 function i have to use since sin is opposite over hypotenuse.

So what i thought to so was Sin -1( 1.75 divided by 4

I came up with 25.94 (rounded slightly)

/ |

4 / |

/ | 1.75

/ |

/ |

/_______|

Can somebody tell me if this is right or not?

So heres the problem:

A cable 4m long is attached to a pole. This cable is staked to the ground 1.75m from the base of the pole. Find the angle that the cable makes with the ground.

I used the bottom left angle as my theta. I think its the Sin -1 function i have to use since sin is opposite over hypotenuse.

So what i thought to so was Sin -1( 1.75 divided by 4

I came up with 25.94 (rounded slightly)

/ |

4 / |

/ | 1.75

/ |

/ |

/_______|

Can somebody tell me if this is right or not?

__________________

C://dos

C://dos.run

run.dos.run

C://dos

C://dos.run

run.dos.run

#

**2**la vache fantôme

Thread Starter

Join Date: Aug 2004

Location: NH

Posts: 6,266

Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 1 Post(s)

eeeh the triangle turned out not so great

__________________

C://dos

C://dos.run

run.dos.run

C://dos

C://dos.run

run.dos.run

#

**3**la vache fantôme

Thread Starter

Join Date: Aug 2004

Location: NH

Posts: 6,266

Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 1 Post(s)

Soh Cah Toa?

**S**means Sin. and oh menas**o**pposite over**h**yp**C**osin and the ah means**a**djacent over**h**yp**T**angent means**o**pposite over**a**djacent
__________________

C://dos

C://dos.run

run.dos.run

C://dos

C://dos.run

run.dos.run

#

**4**la vache fantôme

Thread Starter

Join Date: Aug 2004

Location: NH

Posts: 6,266

Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 1 Post(s)

Yea I can photoshop the triangle

__________________

C://dos

C://dos.run

run.dos.run

C://dos

C://dos.run

run.dos.run

#

**5**la vache fantôme

Thread Starter

Join Date: Aug 2004

Location: NH

Posts: 6,266

Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 1 Post(s)

do you get 25.94 when rounded to the nearest hundred?

__________________

C://dos

C://dos.run

run.dos.run

C://dos

C://dos.run

run.dos.run

#

**6**la vache fantôme

Thread Starter

Join Date: Aug 2004

Location: NH

Posts: 6,266

Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 1 Post(s)

Soh Cah Toa is what every teacher except this one ***** teaches. For hte intro and the trig class

__________________

C://dos

C://dos.run

run.dos.run

C://dos

C://dos.run

run.dos.run

#

**7**la vache fantôme

Thread Starter

Join Date: Aug 2004

Location: NH

Posts: 6,266

Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 1 Post(s)

well in geometry class part of the cericulum is intro to trig. Its supposed to be just 4 days. bUt the teacher i have is the biggest math geek ever and is qualified to teach every math course this school offers. He teaches AP stat and trig, and that is what he is more happy with so instead of 4 days we spend 4 weeks

__________________

C://dos

C://dos.run

run.dos.run

C://dos

C://dos.run

run.dos.run

#

**8**Senior Member

Join Date: Jun 2004

Location: Denver

Posts: 3,698

Bikes:

*2006 custom Walt Works roadie, 2003 Fuji Finest (road), 2002 Giant Iguana (mtb), 1986 BMW K75 (motor)*Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 2 Post(s)

Originally Posted by

**MERTON**what's intro?

Intro.

Phantom is going to intro his boot to Merton's butt.

Intro.

PS: Calc and higher maths are easy if you're solid with algebra and trig

#

**9**la vache fantôme

Thread Starter

Join Date: Aug 2004

Location: NH

Posts: 6,266

Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 1 Post(s)

yea yea i know. IM actually doing well in trig. I enjoy it a hell of a lot more than proofs!

__________________

C://dos

C://dos.run

run.dos.run

C://dos

C://dos.run

run.dos.run

#

**10**Senior Member

Join Date: Jun 2004

Location: Denver

Posts: 3,698

Bikes:

*2006 custom Walt Works roadie, 2003 Fuji Finest (road), 2002 Giant Iguana (mtb), 1986 BMW K75 (motor)*Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 2 Post(s)

for those who don't know, curly hair notation = pubic short-hand.

#

**11**Chronic Tai Shan

Join Date: Oct 2004

Location: PHL/BAL

Posts: 1,118

Bikes:

*Pake Single Speed*Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 0 Post(s)

Some Old Horse Caught Another Horse Taking Oats Away

a/sinA = b/sinB = c/sinC, where A is an angle, and a is side of triangle opposite angle A, and so on.

Works for any triangle.

a/sinA = b/sinB = c/sinC, where A is an angle, and a is side of triangle opposite angle A, and so on.

Works for any triangle.

#

**12**Member

Join Date: Aug 2004

Location: far North Dallas

Posts: 27

Bikes:

*Del Sol Veloz TR; Mongoose Pro Rockadile*Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 0 Post(s)

Originally Posted by

**phantomcow2**Im trying to figure out these stupid inverse functions in trig. I know Soh Cah Toa. And im good with that but now its stuff where instead of being given the value of your angle (theta) and the value of one length and you find the rest. Its 2 lengths and you find the angle.

So heres the problem:

A cable 4m long is attached to a pole. This cable is staked to the ground 1.75m from the base of the pole. Find the angle that the cable makes with the ground.

I used the bottom left angle as my theta. I think its the Sin -1 function i have to use since sin is opposite over hypotenuse.

So what i thought to so was Sin -1( 1.75 divided by 4

I came up with 25.94 (rounded slightly)

/ |

4 / |

/ | 1.75

/ |

/ |

/_______|

Can somebody tell me if this is right or not?

So heres the problem:

A cable 4m long is attached to a pole. This cable is staked to the ground 1.75m from the base of the pole. Find the angle that the cable makes with the ground.

I used the bottom left angle as my theta. I think its the Sin -1 function i have to use since sin is opposite over hypotenuse.

So what i thought to so was Sin -1( 1.75 divided by 4

I came up with 25.94 (rounded slightly)

/ |

4 / |

/ | 1.75

/ |

/ |

/_______|

Can somebody tell me if this is right or not?

what you actually found was the angle the cable makes the pole. in the picture, you drew 1.75m as the height of the pole, instead of the distance from the stake to the base of the pole. which might have confused you. the answer you found is right for the picture you drew. however, since 1.75 is the base of the triagle...what you're looking for is cos^-1(1.75/4) which should give you ~64.06 deg.

#

**13**My life be like ooh aah

Join Date: Apr 2003

Location: Adelaide, Australia

Posts: 1,409

Bikes:

*Giant Boulder SE 2000, Craftworks FRM125 2002*Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 0 Post(s)

Originally Posted by

**phantomcow2**Im trying to figure out these stupid inverse functions in trig. I know Soh Cah Toa. And im good with that but now its stuff where instead of being given the value of your angle (theta) and the value of one length and you find the rest. Its 2 lengths and you find the angle.

So heres the problem:

A cable 4m long is attached to a pole. This cable is staked to the ground 1.75m from the base of the pole. Find the angle that the cable makes with the ground.

I used the bottom left angle as my theta. I think its the Sin -1 function i have to use since sin is opposite over hypotenuse.

So what i thought to so was Sin -1( 1.75 divided by 4

I came up with 25.94 (rounded slightly)

/ |

4 / |

/ | 1.75

/ |

/ |

/_______|

Can somebody tell me if this is right or not?

So heres the problem:

A cable 4m long is attached to a pole. This cable is staked to the ground 1.75m from the base of the pole. Find the angle that the cable makes with the ground.

I used the bottom left angle as my theta. I think its the Sin -1 function i have to use since sin is opposite over hypotenuse.

So what i thought to so was Sin -1( 1.75 divided by 4

I came up with 25.94 (rounded slightly)

/ |

4 / |

/ | 1.75

/ |

/ |

/_______|

Can somebody tell me if this is right or not?

cos theta = 1.75/4

theta = cos^-1 (1.75/4)

Punch that into your calculator and you're done.

#

**14**cab horn

Join Date: Jun 2004

Location: Toronto

Posts: 28,321

Bikes:

*1987 Bianchi Campione*Mentioned: 1 Post(s)

Tagged: 0 Thread(s)

Quoted: 10 Post(s)

We'll easily solve this problem for you.

Go to paint. Draw out the diagram. Save as jpeg. Upload to any webspace and reference it here.

Go to paint. Draw out the diagram. Save as jpeg. Upload to any webspace and reference it here.

#

**15**Senior Member

Join Date: Aug 2003

Location: NE Indiana

Posts: 12,950

Mentioned: 26 Post(s)

Tagged: 0 Thread(s)

Quoted: 2953 Post(s)

Originally Posted by

**phantomcow2**So heres the problem:

A cable 4m long is attached to a pole. This cable is staked to the ground 1.75m from the base of the pole. Find the angle that the cable makes with the ground.

I used the bottom left angle as my theta. I think its the Sin -1 function i have to use since sin is opposite over hypotenuse.

So what i thought to so was Sin -1( 1.75 divided by 4

I came up with 25.94 (rounded slightly)

/ |

4 / |

/ | 1.75

/ |

/ |

/_______|

Can somebody tell me if this is right or not?

#

**16**Chronic Tai Shan

Join Date: Oct 2004

Location: PHL/BAL

Posts: 1,118

Bikes:

*Pake Single Speed*Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 0 Post(s)

Originally Posted by

**MERTON**you can see the pic just fine if you click on his quote button.

#

**17**Chronic Tai Shan

Join Date: Oct 2004

Location: PHL/BAL

Posts: 1,118

Bikes:

*Pake Single Speed*Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 0 Post(s)

Originally Posted by

**MERTON**oh. heh. i really need to start reading.

#

**18**Chronic Tai Shan

Join Date: Oct 2004

Location: PHL/BAL

Posts: 1,118

Bikes:

*Pake Single Speed*Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 0 Post(s)

Originally Posted by

**MERTON**read it first?

#

**19**la vache fantôme

Thread Starter

Join Date: Aug 2004

Location: NH

Posts: 6,266

Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 1 Post(s)

i dont need to use autocad. I get it all now,

__________________

C://dos

C://dos.run

run.dos.run

C://dos

C://dos.run

run.dos.run

#

**20**My life be like ooh aah

Join Date: Apr 2003

Location: Adelaide, Australia

Posts: 1,409

Bikes:

*Giant Boulder SE 2000, Craftworks FRM125 2002*Mentioned: 0 Post(s)

Tagged: 0 Thread(s)

Quoted: 0 Post(s)

Originally Posted by

**ofofhy**The problem is that the diagram in his original post does not match the wording of the problem. It should be like the attached. Anthonaut and apple_quit are right.