Wednesday

July 30, 2014

July 30, 2014

Posted by **LiNnda** on Monday, May 3, 2010 at 11:19am.

- equations trig -
**Reiny**, Monday, May 3, 2010 at 11:50amvery tricky

8sin^2x+sinxcosx+cos^2x=4

8sin^2x+sinxcosx+cos^2x=4(sin^2x + cos^2x)

8sin^2x+sinxcosx+cos^2x=4sin^2x + 4cos^2x

4sin^2x + sinxcosx - 3cos^2x = 0

(sinx + cosx)(4sinx - 3cosx) = 0

sinx = -cosx or sinx = (3/4)cosx

sinx/cosx = -1 or sinx/cosx = 3/4

tanx = -1 or tanx = 3/4

x = 135°, 315° or x = 36.9° or 216.9°

if you want radians, change your calculator to rad

- equations trig -
**LiNnda**, Thursday, May 6, 2010 at 7:53amthank u very much!

**Related Questions**

Trigonometry. - ( tanx/1-cotx )+ (cotx/1-tanx)= (1+secxcscx) Good one! ...

TRIG! - Posted by hayden on Monday, February 23, 2009 at 4:05pm. sin^6 x + cos^6...

equations trig - 1) ctgx+cosx=1+ctgx*cosx 2) sin^4x+cos^4x=1/2 3) (sinx-cosx)^2=...

Trig Proofs! - I'm having trouble solving this proof. Can you help? cos^3+sin^3...

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. Law of Cosines - Show that any triangle with standard labeling... a^2+b^2+...

Math - Solving for Trig Equations - Solve the following equation for 0 less than...

Trigonometry - There is an arbitrary triangle with angles A, B, and C and sides ...

Math - Solving Trig Equations - Solve each equation for o is less than and/or ...