Can't figure this one out ...please help
if sin(4x)cos(4x)= ksin(mx)then what is k+m?
Thanks!
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Trig problem
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Trig problem
by dasaenzjr » Wed Dec 19, 2012 3:47 am
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Re: Trig problem
by darksaber21 » Wed Dec 19, 2012 7:17 am
You need to know the following trig identiy:
[unparseable or potentially dangerous latex formula]
Since in this case b=4, then m = 1/2 and k = 8, making the answer [unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
Since in this case b=4, then m = 1/2 and k = 8, making the answer [unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
Last edited by darksaber21 on Wed Dec 19, 2012 9:45 pm, edited 2 times in total.
Now I know the stakes, and I'm willing to show what I gots. I will see you all at state for the first and final time, so let's end the year with a bang! :)
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MTHS - Class 5A, District VII, Region I
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Re: Trig problem
by nsguy1350 » Wed Dec 19, 2012 7:59 pm
2013 District 1/Region:
NS - 319/355
MA - 340/332
CA - 294/287
SC - 344/292
CS - 212/124 (fail)
NS - 319/355
MA - 340/332
CA - 294/287
SC - 344/292
CS - 212/124 (fail)
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Re: Trig problem
by 101dalmatians » Wed Dec 19, 2012 9:03 pm
better! Use the solver on the 89, plug some value for x and - yeah you get the right answer!
No need of all the work you know...
No need of all the work you know...
I guess this signature really doesn't matter now that I know that the forum is going down soon...
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Re: Trig problem
by dasaenzjr » Wed Dec 19, 2012 9:48 pm
Thanks Guys I just figured it out today using the product to sum properties
sin(x)cos(y)=1/2[sin(x+y) + sin(x-y)] so
sin(4x)cos(4x)= 1/2[sin(4x+4x) + sin(4x-4x)]
= 1/2[sin(8x) + 0]
= 1/2sin(8x)
so 1/2 + 8 = 8.5 = 17/2
sin(x)cos(y)=1/2[sin(x+y) + sin(x-y)] so
sin(4x)cos(4x)= 1/2[sin(4x+4x) + sin(4x-4x)]
= 1/2[sin(8x) + 0]
= 1/2sin(8x)
so 1/2 + 8 = 8.5 = 17/2
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Re: Trig problem
by darksaber21 » Wed Dec 19, 2012 9:50 pm
Now I know the stakes, and I'm willing to show what I gots. I will see you all at state for the first and final time, so let's end the year with a bang! :)
MTHS - Class 5A, District VII, Region I
MTHS - Class 5A, District VII, Region I
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Re: Trig problem
by darksaber21 » Wed Dec 19, 2012 9:52 pm
Now I know the stakes, and I'm willing to show what I gots. I will see you all at state for the first and final time, so let's end the year with a bang! :)
MTHS - Class 5A, District VII, Region I
MTHS - Class 5A, District VII, Region I
- darksaber21
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- Posts: 477
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Re: Trig problem
by 101dalmatians » Sun Dec 30, 2012 12:09 pm
SOLVERS MAN - THEY MAKE LIFE EASIER!!!
JUST TRY IT OUT... YOUR CHOICE BUT MY RECOMMENDATION.
[unparseable or potentially dangerous latex formula] [unparseable or potentially dangerous latex formula]
Come on... I make like mistakes in every test when i am under pressure...
I use the calculator on like 90% of the math test (including #1)...
These questions - i just use the solver and like plug in the values needed.
I believe that all this math takes up a bunch of time!
JUST TRY IT OUT... YOUR CHOICE BUT MY RECOMMENDATION.
[unparseable or potentially dangerous latex formula] [unparseable or potentially dangerous latex formula]
Come on... I make like mistakes in every test when i am under pressure...
I use the calculator on like 90% of the math test (including #1)...
These questions - i just use the solver and like plug in the values needed.
I believe that all this math takes up a bunch of time!
I guess this signature really doesn't matter now that I know that the forum is going down soon...
-
101dalmatians - Ubiquitous Spammer
- Posts: 1013
- Joined: Mon Aug 27, 2012 6:30 pm
- Location: Dallas, Tx.
Re: Trig problem
by nsguy1350 » Sun Dec 30, 2012 4:44 pm
2013 District 1/Region:
NS - 319/355
MA - 340/332
CA - 294/287
SC - 344/292
CS - 212/124 (fail)
NS - 319/355
MA - 340/332
CA - 294/287
SC - 344/292
CS - 212/124 (fail)
- nsguy1350
- Ubiquitous Spammer
- Posts: 1228
- Joined: Fri Jan 27, 2012 4:16 pm
- Location: Dallas, TX
Re: Trig problem
by 101dalmatians » Sun Dec 30, 2012 5:05 pm
yeah that's true too... i'll try.... by the way, the 89 does have a custom solver right?
I guess this signature really doesn't matter now that I know that the forum is going down soon...
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101dalmatians - Ubiquitous Spammer
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- Joined: Mon Aug 27, 2012 6:30 pm
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