Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

**Howardroark****Member**- Registered: 2010-10-10
- Posts: 382

Hi ganesh,

I come from a civilization which has given the world the number 0..

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,000

hi ganesh

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,335

Hi bobbym, Howardroark, and anonimnystefy,

The solution T#13 is perfect. Excellent!

T#14. If sin θ = cos θ and θ is acute, find the value of tan θ.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,793

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,000

hi ganesh

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,335

Hi bobbym and anonimnystefy,

The solution T#14 is correct. Brilliant!

T#15. A flag staff stands on the top of one high tower. From a point on the ground the angle of elevation of the top of the flag staff is 60[sup]o[/sup] and from the same point the angle of elevation of the top of the tower is 45[sup]o[/sup]. Find the height of the flag staff.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,793

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

Offline

**Maiya****Member**- Registered: 2011-08-11
- Posts: 124

Hello Ganesh;

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,335

Hi bobbym and Maiya,

I am sorry I forgot to mention the height of the tower is 6 meters. Regretted!

T#16. A man standing on top of a multistoreyed building 45 meter high is looking at two advertising pillars on the same side whose angles of depression are 30 degrees and 45 degrees. What is the distance between the two pillars?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,793

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

Offline

**Arthur Bon Zavi****Member**- Registered: 2011-10-30
- Posts: 121

*Last edited by Arthur Bon Zavi (2011-10-31 04:54:05)*

In the heart of the night, when it's dark in the lights; I heard the loudest voice - a gun shot on the floor.

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,335

Hi bobbym and Arthur Bon Zavi,

The solution T#16 is correct. (45(√3 - 1)). Excellent, bobbym!

T#17. A surveyor needs to determine the height of a light-house. He measures the angle at A and finds that tan A = 3/4. What is the height of the light-house, if A is 40 meters from the base?

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,793

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**Arthur Bon Zavi****Member**- Registered: 2011-10-30
- Posts: 121

Can you show the working of #16 ?

In the heart of the night, when it's dark in the lights; I heard the loudest voice - a gun shot on the floor.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,793

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**Maiya****Member**- Registered: 2011-08-11
- Posts: 124

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,335

Hi bobbym and Maiya,

The solution T#17 is perfect. Excellent!

T#18. The angle of elevation of the top of a tower at a distance of 50 meters from its foot on horizontal plane is found to be 60[sup]o[/sup]. Find the height of the tower.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,793

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**Maiya****Member**- Registered: 2011-08-11
- Posts: 124

Hello Ganesh;

*Last edited by Maiya (2011-11-09 22:55:40)*

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,335

Hi bobbym and Maiya,

The solution T#18 is perfect. Excellent!

T#19. A ladder is placed against a wall such that it reaches the top of the wall of height 6 meters and the ladder is inclined at an angle of 60[sup]o[/sup] with the ground. Find how far the ladder is from the foot of the wall.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,793

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**Maiya****Member**- Registered: 2011-08-11
- Posts: 124

Hello Ganesh;

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,335

Hi bobbym and Maiya,

The solution T#19 is correct. Brilliant!

T#20. From the top of a lighthouse, the angles of depression of two ships on either sides of the lighthouse are observed as 30[sup]o[/sup] and 45[sup]o[/sup]. If the height of the lighthouse is 200 meters, find the distance between the ships.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,793

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**Maiya****Member**- Registered: 2011-08-11
- Posts: 124

hello Ganesh;

Offline