Find the limit.
-$$\lim _ { P \rightarrow ( 1,1,8 ) } \sec ^ { 2 } x - \tan ^ { 2 } y + z$$
A) 9
B) 8
C) 2
D) 1

Question

Quizplus · Accepted Answer

The given expression simplifies directly by substituting the values of $x$, $y$, and $z$ from the point $P(1,1,8)$. Since $\sec^2 x - \tan^2 y = 1$ for any $x$ and $y$ (based on the trigonometric identity $\sec^2 x - \tan^2 x = 1$), substituting $x = 1$, $y = 1$, and $z = 8$ gives $1 + 8 = 9$.

Find the Limit lim⁡P→(1,1,8)sec⁡2x−tan⁡2y+z\lim _ { P \rightarrow ( 1,1,8 ) } \sec ^ { 2 } x - \tan ^ { 2 } y + zP→(1,1,8)lim​sec2x−tan2y+z

Find the Limit $\lim _ { P \rightarrow ( 1,1,8 ) } \sec ^ { 2 } x - \tan ^ { 2 } y + z$