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Solve the following expression: \sec^2 A + (\csc^2 A - 1) - (1 + \tan^2 A) + \cot^2 A = \text{_______}
2\cot² A
1
\sec² A
0
2\cot² A
Use trigonometric identities to simplify: (cosec² A - 1) = cot² A and (1 + tan² A) = sec² A. Substitute these into the original expression to cancel terms.
Expression to evaluate: sec² A + (cosec² A - 1) - (1 + tan² A) + cot² A
sec2A−tan2A=1,csc2A−cot2A=1
Use trigonometric identities to simplify: (cosec² A - 1) = cot² A and (1 + tan² A) = sec² A. Substitute these into the original expression to cancel terms.
Confusing signs when removing parentheses or misapplying the fundamental Pythagorean identities.
Simplify using identities
We know the identities: csc2A−1=cot2A and 1+tan2A=sec2A. Substitute these into the expression: sec2A+(cot2A)−(sec2A)+cot2A.
sec2A+cot2A−sec2A+cot2A
Group like terms
Group the sec2A terms and the cot2A terms: (sec2A−sec2A)+(cot2A+cot2A).
(sec2A−sec2A)+2cot2A
Calculate final result
The sec2A terms cancel out, leaving 0+2cot2A=2cot2A.
2cot2A
A is correct because the expression simplifies to 2cot² A after applying trigonometric identities.
Trigonometric simplification is a core component of Calculus and Coordinate Geometry. Always look to convert expressions into simpler base terms using fundamental identities like sin2θ+cos2θ=1.