Question

Find five values of theta(in radians) that satisfy the equation sec theta=-2

Answer 1

Explanation:

sec θ=-2

cos θ=-1/2=-cos π/3

=cos(π-π/3),cos(π+π/3)

=cos 2π/3,cos 4π/3

=cos(2nπ+2π/3),cos(2nπ+4π/3)

=cos(6nπ+2π)/3,cos(6nπ+4π)/3

θ=(6nπ+2π)/3,(6nπ+4π)/3

n=0,1,2

θ=2π/3,4π/3,8π/3,10π/3,14π/3,16π/3

Take first value values.