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July 25, 2014

July 25, 2014

Posted by **applebottom** on Friday, November 5, 2010 at 8:05pm.

tan^2(x)+0.8 tan(x)-3.84 = 0

- math -
**Damon**, Friday, November 5, 2010 at 8:43pmlet z = tan x

z^2 +.8 z -3.84 = 0

z = [ -.8 +/- sqrt (.64 +15.36)]/2

z = [ -.8 +/- sqrt (16) ] / 2

z = [ -.8 +/- 4 ]/2

z = tan x = -2.4 or -1.6

tan is negative in quadrants 2 and 4

so

about -1 radian or about -1.18 radian

which is 2 pi - 1 and 2 pi - 1.18

also pi -1 and pi - 1.18

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