Answer:
A. -2sin(x)sin(0.4x)
Step-by-step explanation:
At x=0, the given expression evaluates to zero.
For x near zero, the given expression is slightly negative. You know this because cos(1.4x) decreases faster than cos(0.6x), so their difference will be negative.
Of the answer choices, you can eliminate C and D because they are not zero at x=0. You can eliminate choice B, because it is positive for values of x near zero. The only viable choice is A:
-2sin(x)sin(0.4x)
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Of course, a graphing calculator can help you figure this out. See the attachment. The given expression is plotted using a solid red line; the answer choice A is plotted using blue dots.
CB = DA = √3*3+1*1 = √10
CD = BA = √2*2+1*1 = √5
Sum is 2√10 + 2√5 ≈ 10.8. So answer A.
The interquartile range is 20 you take Q3 in the graph which is 30 and the Q1 in the graph which is 10 then you subtract Q3-Q1 so 30-10 and get 20
Answer: D.)
Step-by-step explanation:
Add the rates. 3:1 (3+1)=4
multiply it to the rate. 3(4), 1(4) = 12 and 4
Side a is 12 inches long and side b is 4 inches long.