Answer:
Option 3 is right.
Step-by-step explanation:
Reference angle of x is obtained by either 180-x, 180+x. or 360-x depending on the posiiton of terminal whether II quadrant or iv quadrant, or iii quadrant, etc.
In whatever way we find reference angles,
cos will remain cos only and sin will remain sin only there may be only changes in sign.
Of all the ordered pairs given, we find that I, II, and Iv there is a switch over form cos to sine and sin to cos. Hence these options cannot be for reference angles.
III option is 
show that both sign and cos changed sign. This is possible only in III quadrant.
ie reference angle of orignal angle t = 180+t
SO this option is right.
In this item, it is unfortunate that a figure, drawing, or illustration is not given. To be able to answer this, it is assumed that these segments are collinear. Points L, M, and N are collinear, and that L lies between MN.
The length of the whole segment MN is the sum of the length of the subsegments, LN and LM. This can be mathematically expressed,
LN + LM = MN
We are given with the lengths of the smalller segments and substituting the known values,
MN = 54 + 31
MN = 85
<em>ANSWER: MN = 85</em>
Answer:
Option D
Step-by-step explanation:
The questions which involve calculating the angles and the sides of a triangle either require the sine rule or the cosine rule. In this question, the two sides that are given are adjacent to each other the given angle is the included angle. This means that the angle B is formed by the intersection of the lines a and c. Therefore, cosine rule will be used to calculate the length of b. The cosine rule is:
b^2 = a^2 + c^2 - 2*a*c*cos(B).
The question specifies that c=71, B=123°, and a=65. Plugging in the values:
b^2 = 65^2 + 71^2 - 2(65)(71)*cos(123°).
Simplifying gives:
b^2 = 14293.0182932.
Taking square root on the both sides gives b = 119.6 (rounded to the one decimal place).
This means that the Option D is the correct choice!!!
Answer:
E(X) = 1.28
Var(X) = 0.6016
E(X | Y=2) = 1.6667
Var(X | Y=2) = 0.4272
Step-by-step explanation: