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# exact value of tan theta? watch

1. How exactly would I approach a problem such as the following?

θ is an acute angle with sin θ = 15/43. Find the exact value
of tan θ.

Edit: Nevermind - decided to think outside the triangle.
2. (Original post by BestProfileName)
How exactly would I approach a problem such as the following?

θ is an acute angle with sin θ = 15/43. Find the exact value
of tan θ.

Edit: Nevermind - decided to think outside the triangle.
Just sketch a right angled triangle with one side =15 and hypotenuse =43
3. Just in case the PM didn't work:
A boat has a speed of 4ms^(-1) (relative to the surrounding water) and a heading of 170 degree.

There is a current flowing from a bearing of 105 degree at a speed of 2.5ms^(-1). Take i to point east

and j to point north.

I have tried to draw the triangle but, which ends up with the unknown side pointing to the southwest, but then the hypotenuse is the shortest side and the question seems to suggest that it should be pointing to the southeast - I therefore think I don't understand bearings.

When it says "from a bearing" is that different to "on" a bearing? And how would that look in a triangle?
4. (Original post by BestProfileName)
Just in case the PM didn't work:
A boat has a speed of 4ms^(-1) (relative to the surrounding water) and a heading of 170 degree.

There is a current flowing from a bearing of 105 degree at a speed of 2.5ms^(-1). Take i to point east

and j to point north.

I have tried to draw the triangle but, which ends up with the unknown side pointing to the southwest, but then the hypotenuse is the shortest side and the question seems to suggest that it should be pointing to the southeast - I therefore think I don't understand bearings.

When it says "from a bearing" is that different to "on" a bearing? And how would that look in a triangle?
Is there more to the question ... Well is there an actual question
5. (Original post by TenOfThem)
Is there more to the question ... Well is there an actual question
Sure:
"Express the velocity U of the boat relative to still water and thevelocity w of the current in component form, giving numerical values
in ms−1 to one decimal place."

The issue I'm really having is drawing the triangle. I'd expect the unknown side to be the longest if it's the hypotenuse, but when I draw it, that side appears to be smaller.
6. (Original post by BestProfileName)
Sure:
"Express the velocity U of the boat relative to still water and thevelocity w of the current in component form, giving numerical values
in ms−1 to one decimal place."

The issue I'm really having is drawing the triangle. I'd expect the unknown side to be the longest if it's the hypotenuse, but when I draw it, that side appears to be smaller.
There is no right angled triangle so there is no hypotenuse
7. (Original post by TenOfThem)
There is no right angled triangle so there is no hypotenuse
Now this is what I thought and my googling provided no answer. Thanks!

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