If sin2x=7/25, siny=-2/sq root of

If sin2x=7/25, siny=-2/sq root of 13, cot y>0, and -pi/4<x<pi/4, find sin(2y-a)
1. 2 answers
2. asked by Liv
3. 493 views
How do I get (sinx cosy + cosx siny) (cosx cosy + sinx siny) in the form of 1/2(sin2x + sin2y)?
1. 1 answer
2. asked by Anonymous
3. 673 views
cosx+cosy=a and sinx+siny=b show that sin2x+sin2y=2ab(1-(2/(a^2+b^2))plz plz show step
1. 7 answers
2. asked by maths
3. 1,905 views
if sin2x=3sin2y,prove that: 2tan(x-y)=tan(x+y) ( here, in sin2x, 2x is an angle., like there's a formula:sin2x=2sinxcosx and
1. 7 answers
2. asked by aayush
3. 3,418 views
Verify each identitysin^x+siny/sinx-siny=tan(x+y/2) (times) cot(x-y/2)
1. 0 answers
2. asked by angel
3. 504 views
Find y'(x) when cos y - y^2 = 8a) -siny - 2y b) - (1/sin y - 2y) c) 0 d) - (8/cos y - y) So if I implicitly differentiate: y'(x)
1. 2 answers
2. asked by Donna
3. 543 views
find the range ofsin(siny)+cos(siny)
1. 0 answers
2. asked by Anonymous
3. 384 views
How can the following two identities be verified?1. (cos^2y)/(1-siny)=1+siny 2. sin^2a-sin^4a=cos^2a-cos^4a Thanks! change
1. 0 answers
2. asked by Corin
3. 555 views
Simplify:sin(x-y)cosy+cos(x-y)siny = (sinxcosy-cosxsiny)cosy+(cosxcosy+sinxsiny)siny = ??? What do I do next??? Please Help and
1. 4 answers
2. asked by Anonymous
3. 1,431 views
Okay, I've been getting some of these, but I can't seem to verify this identity... any help? Here's the problemSin(x+y) +
1. 2 answers
2. asked by Alex
3. 709 views