As you progress in math, it will become increasingly important that you know how to express exponentiation properly.
y = 2x3 – x2 – 4x + 5 should be written <span>y = 2^x3 – x^2 – 4^x + 5. The
" ^ " symbol denotes exponentiation.
I see you're apparently in middle school. Is that so? If so, are you taking calculus already? If so, nice!
Case 1: You do not yet know calculus and have not differentiated or found critical values. Sketch the function </span>y = 2x^3 – x^2 – 4^x + 5, including the y-intercept at (0,5). Can you identify the intervals on which the graph appears to be increasing and those on which it appears to be decreasing?
Case 2: You do know differentiation, critical values and the first derivative test. Differentiate y = 2x^3 – x^2 – 4^x + 5 and set the derivative = to 0:
dy/dx = 6x^2 - 2x - 4 = 0. Reduce this by dividing all terms by 2:
dy/dx = 3x^2 - x - 2 = 0 I used synthetic div. to determine that one root is x = 2/3. Try it yourself. This leaves the coefficients of the other factor, (3x+3); this other factor is x = 3/(-3) = -1. Again, you should check this.
Now we have 2 roots: -1 and 2/3
Draw a number line. Locate the origin (0,0). Plot the points (-1, 0) and (2/3, 0). This subdivides the number line into 3 subintervals:
(-infinity, -1), (-1, 2/3) and (2/3, infinity).
Choose a test number from each interval and subst. it for x in the derivative formula above. If the derivative comes out +, the function is increasing on that interval; if -, the function is decreasing.
Ask all the questions you want, if this explanation is not sufficiently clear.
Answer: 24
Step-by-step explanation:
Basically you just need to add the sides up to get your answer, its like breaking it up and adding simply.
You need to find what 27% of $125 is.
To find a percent of a number, multiply the percent by the number.
27% of $125 =
= 27% * $125
= 0.27 * $125
= $33.75
Answer: Jill spent $33.75 on the shoes.
Answer: The area of rectangle WXYZ is 18 square inches
Step-by-step explanation: Since both rectangles are similar, then lines AD and BC has a common ratio with lines WZ and XY. If line line AD is 10 inches, and line XY is 5 inches, then the ratio of similarity is given as
Ratio = 10/5
Ratio = 2/1 (or 2:1)
However rectangle ABCD has its area as 70 square inches, which means the other side is given as
Area = L x W
70 = 10 x W
70/10 = W
7 = W
Therefore the width of the other rectangle is determined as,
10/5 = 7/W
10W = 5 x 7
10W = 35
Divide both sides of the equation by 10
W = 3.5
Having calculated the width of the other rectangle as 3.5, the area is now determined as
Area = L x W
Area = 5 x 3
Area = 17.5
Rounded off to the nearest integer, the area equals 18 square inches
