ANSWER
True
EXPLANATION
The given trigonometric equation is:
[tex] { \tan}^{2} x + 1 = { \sec}^{2} x[/tex]
We take the LHS and simplify to arrive at the RHS.
[tex]{ \tan}^{2} x + 1 = \frac{{ \sin}^{2} x}{{ \cos}^{2} x} + 1[/tex]
Collect LCM on the right hand side to get;
[tex]{ \tan}^{2} x + 1 = \frac{{ \sin}^{2} x + {\cos}^{2} x}{{ \cos}^{2} x} [/tex]
This implies that
[tex]{ \tan}^{2} x + 1 = \frac{1}{{ \cos}^{2} x} .[/tex]
[tex]{ \tan}^{2} x + 1 = {( \frac{1}{ \cos(x) }) }^{2} [/tex]
[tex]{ \tan}^{2} x + 1 = { \sec}^{2} x[/tex]
This identity has been verified .Therefore the correct answer is true.