Answer:
- x ≈ -0.107760269824
- x ≈ 1.98779489573
Step-by-step explanation:
The quadratic portion of f(x) factors as (-4x)(x -2), so has zeros at x=0 and x=2. The cosine portion of f(x) will have a value of 1 at x=0 and a value of about -0.15 at x=2. Thus, we might expect roots to be slightly negative and near x=2. (It turns out that a not-unreasonable approximation of the cosine function as cos(x) ≈ 1-x²/2 can be usefully used to get better approximations of the roots in each case.)
A graphing calculator makes it easy to find initial approximations of the two roots. The graph shows them to be -0.108 and 1.988.
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Many graphing calculators also include the ability to determine a numerical value of the derivative of a function. This makes it possible to write an iteration function after the fashion of Newton's Method iteration:
g(x) = x -f(x)/f'(x)
where g(x) gives a new value for old guess x, and f'(x) is the derivative of f(x).
The calculator we used is interactive, so the value of g(x) is found even as you type the argument value x. That makes it possible to achieve full calculator accuracy for the root estimate simply by copying the approximate value into the expression g(x).
x ∈ {−0.107760269824, 1.98779489573}
Interval notation is used to write a set of real numbers from one value to another value.
On the left, you start with left parenthesis or left bracket.
Then you follow by two numbers separated by a comma.
You then finish with a right parenthesis or right bracket.
To include a number, use a square bracket.
To exclude a number use parenthesis.
To write the set of numbers, you need to list the smallest number in the set followed by the largest number in the set. An interval is always stated with two numbers, from the smallest in the set to the largest in the set. The numbers are always separated by a comma.
Examples:
1) All numbers from 6 to 10, including 6 and 10.
Algebra: 6 <= x <= 10
Interval: [6, 10]
Notice brackets since both 6 and 10 are included in this interval.
2) All number from 5 to 20, including 5 but not including 20.
Algebra 5 <= x < 20
Interval: [5, 20)
Bracket with 5 means include 5. Parenthesis with 20 means 20 is not included.
3) All numbers greater than or equal to 7.
Algebra: x >= 7
Interval: [7, ∞)
The 7 has a bracket because it is included. Infinity always has parenthesis.
With the infinity symbol, always use parenthesis, not square bracket.
4) All numbers less than -5.
Algebra: x < - 5
Interval: (-∞, 5)
Now for your problems.
10.
This is a line. Both the domain and range all all real numbers.
That means the interval is from negative infinity to positive infinity.
(-∞, ∞)
Both the domain and range are that same interval, all real numbers, from negative infinity to positive infinity.
13.
The domain is all real numbers as you can see the x-coordinates extend left forever and right forever. The domain is the same interval as the domain and range of problem 10.
The range is zero and all positive numbers.
You can think of it a all values of y such that y is greater than or equal to zero. Notice that zero is included in the interval.
[0, ∞)
Since zero is included, we use a left bracket, not left parenthesis.
With infinity, we alyways use parentheses, not brackets.
Answer: 1/250
Step-by-step explanation:
Given the recurring decimal : 0.004
Firstly:
Let x = 0.004 - - - (1)
Due to the number of decimals places and value of x;
We multiply (1) by 1000 to obtain an integer
Multiply (1) by 1000
1000x = 4 - - - (2)
From (2) we can solve for x and leave our answer as a fraction.
Divide (2) by 1000 to obtain the value of x
1000x / 1000 = 4 / 1000
x = 1 / 250
Recall x = 0.004
Therefore, x = 0.004 = 1/250
Answer:
Step-by-step explanation:
Yara=x goals
Natasha= x+8
Emma=2x
Add these
X+x+8+2x=4x+8
4x+8=52 -8
-8 both sides
4x=44
X=11
Yara 11 goals
Natasha 9 goals
Emma 11×2=22 goals hope this helps