It is incorrect because when you times a negative by a positive. It is a negative number.
Trigonometric functions which are related by having the same value at complementary angles are called cofunctions. Cofunctions of complementary angles are equal.
A. csc 20' = csc(90-70)=sec 70
B. cos 87' = cos (90-3)=sin 3'
C. csc 40' = csc(90-50) =sec50'
D. tan 15' = tan(90-75)= cot 75'
Among all the option c is not correct.
Option C is false.
Answer: Choice C
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Explanation:
There are four marked points on the line.
Each point is of the form (x,y)
- The first or left most point is (0,1)
- The second point is (2,2)
- The third is (4,3)
- The fourth is (6,4)
Each of these points is then listed in the table format as shown above.
There are infinitely many other points on the line; however, we only select a few of them to make the table (or else we'd be here all day).
Extra side notes:
- The slope of this line is m = 1/2 = 0.5
- The y intercept is 1 located at (0,1)
- The equation of this line is y = 0.5x+1