Answer:
see explanation
Step-by-step explanation:
Using the trigonometric identity
sin²x + cos²x = 1
Consider the left side
2cos²A - 1 ← replace 1 by sin²A + cos²A
= 2cos²A - ( sin²A + cos²A)
= 2cos²A - sin²A - cos²A
= cos²A - sin²A = right side ⇒ verified
If complex coefficients are allowed, the answer is 3.
If the polynomial must have real coefficients, then each complex root comes as a pair of complex conjugate roots.
Root -5 is real, so that is 1 root, and degree 1.
Root 1 + 4i is complex, so it must come with its complex conjugate, 1 - 4i. This adds 2 roots to the polynomial, and now we're up to degree 3.
Root -4i is also complex. It also must come with its complex conjugate, 4i. That adds two more roots, and the degree is 5.
Answer: The least possible degree is 5 with real coefficients.
Since one kilometer is equal to about 0.621 miles, a runner travels 3.105 miles in a five-kilometer race.
B Beacuse b best fits the suituation
Answer:
Step-by-step explanation: The domain of the expression is all real numbers except where the expression is undefined
