Act Math Practice
Trigonometry Answer 1
© 2008 ACT-Math-Practice.com
Trigonometry Answer 1:
1. Consider the laws of sines and cosines.
(sin
A
)
2
= ?
A. 1 - (cos
A
)
2
B. (cos
A
)
2
- 1
C. (tan
A
)
2
D. 1 - (tan
A
)
2
E. (tan
A
)
2
- 1
The correct answer is C.
Remember the following formulas. They are valid with respect to any angle:
sin
2
+ cos
2
= 1
cos
2
= 1 - sin
2
sin
2
= 1 - cos
2
Therefore, sin
2
is always equal to 1 - cos
2
.
Leave Trigonometry Answer 1 and Return to the ACT Math Scores Page