Trigonometry Quiz

The questions are based on the figure below: 

Record your answers

1.) The area of the triangle is given by ... 

A   $A = ½ (a+b)c$
B   $A = ½ a · b$
C   $A = ½ a · c$
D   $A = a2 + b2 - c2$

2.) Which expression is wrong: 

A   $c2 = a2 + b2$
B   $c2 - a2 = b2$  
C   $b2 - c2 = a2$
D   $b2 - a2 + 2a2 = c2$  

3.) Which expression regarding the values of the angles is right: 

A   $α + β < 90^\circ$ 
B   $α + β > 90^\circ$ 
C   $180^\circ + (α + β) = 360^\circ$ 
D   $180^\circ - α = 90^\circ + β$ 

4.) If the length of side c is 13 cm, the length of side a is 5 cm, what will be the length of side b? 

A   7 cm 
B   8 cm 
C   12 cm 
D   18 cm 

5.) Which expression is correct? 

A   $\sin β = c/b$ 
B   $\sin β = b/a$
C   $\sin α = b/c$ 
D   $\sin α = a/c$

6.) Spot the mistake: 

A   $\sin β = b/a$ 
B   $\sin α = a/c$
C   $\cos β = a/c$ 
D   $\cos α = b/c$ 

7.) Identify the wrong expression: 

A   $a = c · \sin α$ 
B   $a = c · \cos α$  
C   $b = c · \sin β$  
D   $a = c · \cos β$ 

8.) The tan of angle $β$ is given by ... 

A   $\tan β = b/a$ 
B   $\tan β = a/b$ 
C   $\tan β = b/c$
D   $\tan β = a/c$ 

9.) The sin of $30^\circ$ is ... 

A   1 
B   2/3  
C   1/2 
D   1/4  

10.) The cos of $60^\circ$ is the same as ... 

A   $\tan 45^\circ$  
B   $\tan 60^\circ$  
C   $\sin 30^\circ$ 
D   $\sin 60^\circ$