13 articles trouvés pour ce sujet.
|
|
|
|
|
|
|
|
Solve for theta |
2014-04-25 |
|
ALASTAIR pose la question : Hi, The question asks Solve for 'theta' cos2theta=sintheta x costheta.
Substituting for cos2th either 1-2sin^2th or 2cos^2th does not give an equation in either sine or cosine alone how do I solve this please? Penny Nom lui répond. |
|
|
|
|
|
A trig identity |
2013-01-04 |
|
Tehmas pose la question : Prove sinC+sinD=2sin(C+D/2)cos(C-D/2) Harley Weston lui répond. |
|
|
|
|
|
sin(3a), cos(3a) and tan(3a) |
2007-02-28 |
|
mailene pose la question : hi, i...indeed,to..need..your..help how..cn..i..prove..this,formula??? sin3a=3sina-4sin^3a cos3a=4cos^3-3cosa tan3a=3tan-tan^3a /1-3tan^2a the..symbol...^is..the..expOnent Haley Ess and Penny Nom lui répond. |
|
|
|
|
|
cos(3X) |
2006-03-29 |
|
Joshua pose la question : I'm having trouble proving that cos(3X)=cos3X -(cosX)(sin2 X) Penny Nom lui répond. |
|
|
|
|
|
sin(3A) |
2004-10-20 |
|
A student pose la question : Express sin3A in terms of sinA and cosA. Penny Nom lui répond. |
|
|
|
|
|
Some trig expressions |
2004-05-23 |
|
A student pose la question : Prove:
sin A + sin B = 2sin(A+B/2)cos(A-B/2)
cos A - cos B = -2sin(A+B/2)sin(A-B/2)
cos A + cos B = 2cos(A+B/2)cos(A-B/2)
sin A - sin B = 2cos(A+B/2)sin(A+B/2) Penny Nom lui répond. |
|
|
|
|
|
A rule with a variable |
2003-08-24 |
|
Crystal pose la question : what is a rule with a variable Penny Nom lui répond. |
|
|
|
|
|
The area of a circle |
2002-06-03 |
|
Jessica pose la question : I am doing a maths assigment for university, which is aimed towrds primary school students(k-6). I was wondering if you could give me some information as to how I could describe to students the rule for finding the area of circle, using a circle cut up into equal sectors (like a pizza). I know it has something to do with the fact that you can make these shapes into a parallelogram, but I am a bit uncertain as to how I can express this idea clearly and articulately to students. Penny Nom lui répond. |
|
|
|
|
|
sin 2x = cos 3x |
2002-02-25 |
|
Allan pose la question : solve: sin 2x = cos 3x Primary question: how do you handle the cos 3x? Paul Betts and Chris Fisher lui répond. |
|
|
|
|
|
Rewriting and evaluating formulas |
2001-11-19 |
|
A conserned mother pose la question : Due to the wide range of temperatures experienced in Canada, engineers who construct roads must allow for expansion and contraction of the road surface. The following formula is used to calculate the amount of expansion E to allow for: E= kL(T-t), where k is the constant of expansion for the road surface. L is the length of the section of highway in metres. T is the temperature of the air in degrees Celsius. t is the temperature, in degress Celsius, at which the section of the highway was constructed. Walter Whiteley lui répond. |
|
|
|
|
|
Triple angle formula |
2000-02-23 |
|
Sara pose la question : Can one derive a triple angle formula for sine and cosine? If so, how? Chris Fisher lui répond. |
|
|
|
|
|
A Trigonometry Question |
1999-08-28 |
|
Diane Simms pose la question : My question is can the following be factored. I am a teacher who needs the factors to this right away. 2 Sin2X + 2 SinX CosX - 1= 0 Harley Weston lui répond. |
|
|
|
|
|
Equivalent Expressions |
1997-02-26 |
|
Karyn Jones pose la question : Josie says that s=n/(n+1) and s/(1-s)=n are two ways to write the same formula. Describe whether or not you agree with Joise. Explain how you made your decision. Walter Whiteley and Penny Nom lui répond. |
|
|