tan (270° + α )
is gelijk aan
|
A. tan α |
|---|
| B. − tan α |
| C. cot α |
| D. − cot α |
| E. − tan (90° + α) |
[ 3-5320 - op net sinds 11.2.13-(E)-3.11.2023 ]
Translation in E N G L I S H
tan (270° + α )
is equal to
|
A. tan α |
|---|
| B. − tan α |
| C. cot α |
| D. − cot α |
| E. − tan (90° + α) |
Oplossing - Solution
1ste manier : eerst supplement
tan (270° + x) = tan (90° + x) = cot [ 90° − (90° + x) ] = cot (−x) = − cot x
2de manier : eerst − 360°
tan (270° + x) = tan (− 90° + x) = − tan(90° − x) = − cot x
3de manier : eerst complement
tan (270° + x) = cot [ 90° − (270° + x) ] = cot (−180° − x) = cot (−x) = − cot x
