Solve the equation by completing the square round to the nearest hundredth is necessary x^2-x-7=0
1 answer:
The answers are 3.19 or -2.19.
In order to complete the square, you must first get the constant to the other side of the equation. WE do that by adding 7 to both sides.
x^2 - x - 7 = 0
x^2 - x = 7
Now we must take half of the x coefficient (-1), which would be -.5. Then we square it and add it to both sides. This is the second step to any completing the square problem.
x^2 - x = 7
x^2 - x + .25 = 7.25
Now that we have done that, the left side will be a perfect square so that, we can factor it.
x^2 - x + .25 = 7.25
(x - .5)^2 = 7.25
After having done that, we can take the square root of both sides
(x - .5)^2 = 7.25
x - .5 = +/-
Now we can take the value of that square root and solve.
x - .5 = +/-
x - .5 = +/-2.69
x = .5 +/- 2.69
And with the + and - both there, we need to do both to get the two answers.
.5 + 2.69 = 3.19
.5 - 2.69 = -2.19
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The general equation of a cosine function with an amplitude of 3, a period of 4 π, and a horizontal shift of negative π is .
A function is a rule that relates two variables.
The parent function is:
We know the period of the parent function is 2π and the amplitude is 1.
For an amplitude of 3, we need to multiply the parent function by 3.
So, the function with amplitude 3 will be given by:
For a period of 4π, we need to make the argument of the parent function half.
So,
A horizontal shift of negative π means, f(x) will become f(x+π)
So, .
Therefore, the general equation of a cosine function with an amplitude of 3, a period of 4 π, and a horizontal shift of negative π is .
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