I would convert -2pi / 3 to degrees first by multiplying by 180degrees / pi. It equals 120 degrees.
120 degrees is in quadrant II, which is 90 degrees plus 30 degrees. It is 60 degrees from the 180 degrees.
So the reference triangle you use is 60 degrees.
Cos60 = 0.5
sin60 = sqrt(3) /2
But in quadrant II the only trig ratio that's positive is sin; all others are negative.
So cos120 = -0.5
sin60 = sqrt(3) /2
<span>Keeping in mind that points on unit circle are (cos, sin), the point is </span>(-0.5, <span>sqrt(3) /2).
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Answer: yes, she did made an error, a very big mistake.
Step-by-step explanation:
first, we have varieties of ways in which we can use to solve this, the most important thing is to stick to the mathematical rules of solving any equations.
using the most simpler method
-4x + 11 = 6x + 1
collect like ter
-4x -6x = 1 - 11
-10x = -10
divide bothside by -10
-10x/-10 = -10/-10
x=1
secondly, using the method she is intending to use, its more easier to subtract 6x from bothside
-4x + 11 = 6x +1
-6x -6x
_______________
-10x + 11 = 1
-10x = 1-11
-10x = -10
x = 1
or still we can doing it exactly as she did, but it will take us through a long way i.e by adding +6
-4x + 11 = 6x + 1
+6x +6x
_______________
2x +11 = 12x +1
2x-12x = 1-11
-10x=-10
x=1
Answer:
manipulated variable or the independent variable
Step-by-step explanation: