Posted by **please help now** on Sunday, February 26, 2012 at 12:58pm.

Solve for x if sin2x=cos(x+60 and x€ [-90,180].show all work details

- trig -
**drwls**, Sunday, February 26, 2012 at 1:40pm
What does x€ [-90,180] mean?

The domain limits of x?

You seem to have omitted a parenth after x+60

cos(x+60) = sin(90-x-60)

= sin (30-x)

sin2x = sin(30-x)

Therefore 2x = 30 -x

x = 10 degrees is one solution

See if you can find others. Note that sin2x = sin(180 -2x); that will lead to another solution.

- trig -
**please help now**, Monday, February 27, 2012 at 12:49pm
Yes it mean domaim limit of x that guied u when plot the graph

## Answer This Question

## Related Questions

- math - given f(x)=sin2x and g(x)=cos(x+30) 1. solve for x if sin2x=cos(x+30) for...
- Trig (Last URGENT) - sin2x+cosx=0 , [-180,180) = 2sinxcosx+cosx=0 = cosx(2sinx+1...
- pre-calc - Solve: cos(2x-180) - sin(x-90)=0 my work: cos2xcos180 + sin2xsin180= ...
- Trig - A. Find simpler, equivalent expressions for the following. Justify your ...
- math - Solve for x if sin2x=cos(x+30) for x [-180;180]
- Math - Solving Trig Equations - What am I doing wrong? Equation: sin2x = 2cos2x ...
- math (trig) - i have some problems doing trig the first one is: Show that cos(x/...
- trig - I am very confused about the concepts of.. sin è = sin(180 - è) sin (180...
- trig - tanx = 5/12 and sinx<0 Find sin2x and cos2x How to get the answers of ...
- Math - Solving for Trig Equations - Solve the following equation for 0 less than...

More Related Questions