Question 21019
tan2(4)−sec2(4)= Answer.-1.
B is the midpoint of line AC. AB=5x and BC=2x+3. Find AB, BC, and AC.
Solution.
Since
sec2(x)=cos2(4)1, then using the equality cos2(4)+sin2(4)=1, we get
sec2(4)=cos2(4)cos2(4)+sin2(4)=1+tan2(4).
Finally,
tan2(4)−sec2(4)=tan2(4)−(1+tan2(4))=−1
Answer. -1.