Answer:
Step-by-step explanation:
You know that ...
- cos(θ)² = 1 - sin(θ)²
- tan(θ) = sin(θ)/cos(θ)
- cosine is negative in the third quadrant (where π < θ < 3π/2)
Using what you know about the relationships of these trig functions, you can find ...
cos(θ)² = 1 - ((-√3)/2)² = 1 - 3/4 = 1/4
cos(θ) = -1/2 . . . . . negative square root of 1/4
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tan(θ) = sin(θ)/cos(θ) = ((-√3)/2)/(-1/2)
tan(θ) = √3
Pythagoras theorem is c^2 = b^2 + a^2
so when you plug in the numbers its 12^2 + 5^2 =169
which means 144+24=169
square root 169 = 13
AB =13 cm
hope this helps I tried my best. xx
Adding you make it the opposite of