Answer:
see explanation
Step-by-step explanation:
Using the sum/ difference → product formula
cos x - cos y = - 2sin( )sin (
)
sin x - sin y = 2cos ( )sin (
)
Given
(cosA - cosB)² + (sinA - sinB )²
= [ - 2sin()sin(
) ]² + [ 2cos(
)sin(
) ]²
= 4sin² ( )sin² (
) + 4cos² (
)sin² (
)
= 4sin² ( )[ sin² (
) + cos² (
) ← sin²x + cos²x = 1
= 4sin² ( ) × 1
= 4sin² ( ) = right side ⇒ proven
Answer:
Th computed value of the test statistic is 3.597
Step-by-step explanation:
The null and the alternative hypothesis is as follows:
Null Hypothesis:
the population correlation coefficient is equal to zero
the population correlation coefficient is not equal to zero
The test statistics for Pearson correlation coefficient is thus computed as :
where;
r = correlation coefficient = 0.60
n = sample size = 25
So;
t = 3.597
Comparing to a critical value of t (23 degrees of freedom two-tailed value) = 2.069
Decision Rule:
Since computed value of t is greater than the critical value of t; We reject the null hypothesis and accept the alternative hypothesis.
Conclusion:
We conclude that the population correlation coefficient significantly differs from 0 at 5% (0.05) level of significance.