Mathématiques du secondaire qualifiant
Calcul trigonométrique (1_8)
Exercice 1 tp
Calculer
| a = cos( |
23π |
+15π) |
| 4 |
| b = sin(5π- |
3π |
) |
| 4 |
Correction
| a = cos( |
23π |
+15π) = cos(π- |
3π |
) |
| 4 |
4 |
| Donc a = -cos |
3π |
= - |
√(2) |
| 4 |
2 |
| b = sin( 5π - |
3π |
) |
| 4 |
| = sin(π- |
3π |
) |
| 4 |
| donc b = sin |
3π |
= |
√(2) |
| 4 |
2 |
Exercice 2 tp
Calculer
| cos²( |
7π |
+15π) + sin²(3π- |
3π |
) |
| 5 |
5 |
Exercice 3 tp
Calculer
Correction
| a = cos( |
27π |
+ |
π |
) |
| 2 |
3 |
| = cos( |
28π-π |
+ |
π |
) |
| 2 |
3 |
ou encore
| = cos( |
-π |
+ 14π + |
π |
) |
| 2 |
3 |
| = cos( |
-π |
+ |
π |
) |
| 2 |
3 |
| = cos( |
π |
- |
π |
) |
| 2 |
3 |
Exercice 4 tp
Calculer
| a = sin( |
5π |
- |
π |
) |
| 2 |
4 |
| b = cos( |
5π |
+ |
π |
) |
| 2 |
3 |
Correction
| a = sin( |
5π |
- |
π |
) |
| 2 |
4 |
| = sin( |
4π+π |
- |
π |
) |
| 2 |
4 |
ou encore
| a = sin( |
π |
+ 2π - |
π |
) |
| 2 |
4 |
| = sin( |
π |
- |
π |
) |
| 2 |
4 |
| donc, a = cos |
π |
= |
√(2) |
|
| 4 |
2 |
Ou encore
| b = cos( |
4π+π |
+ |
π |
) |
| 2 |
3 |
| = cos( |
π |
+ 2π + |
π |
) |
| 2 | 3 |
| = cos( |
π |
+ |
π |
) |
| 2 |
3 |
| donc b = -sin |
π |
= |
- √(3) |
|
| 3 |
2 |