How do I solve 2sec^2x + tan^2x-3=0 ?

1 Answer
Apr 25, 2018

See below

Explanation:

Apply trig identity:
#1+tan^2x=sec^2x#

So:
#2sec^2x + tan^2x-3=0#

#2(1+tan^2x)+tan^2x-3=0#

#2+2tan^2x+tan^2x-3=0#

#3tan^2x-1=0#

#tan^2x=1/3#

#tanx= +-sqrt3/3#

#x=pi/6+-pin#
#x= (5pi)/6+-pin#
Where n is an element of all real numbers

graph{2(secx)^2+(tanx)^2-3 [-10, 10, -5, 5]}