<span><span> <span>Akar akar persamaan kuadrat 2x² - 3x -1 = 0 adalah x1 dan x2. Persamaan kuadrat baru yang akar akarnya satu lebih kecil dari dua kali akar akar persamaan kuadrat di atas adalah ........</span></span><span><span><span>A.x² - x - 4 = 0</span><span>B.x² + 5x - 4 = 0</span><span>C.x² - x + 4 = 0</span></span><span><span>D.x² + x + 4 = 0</span><span>E.x² - 5x - 4 = 0</span></span></span><span>Jawaban : A
Penyelesaian :
Akar-akar persamaan lama : x1 dan x2
Akar-akar persamaan baru : xA dan xB
xA = 2x1 - 1
xB = 2x2 - 1
xA + xB = (2x1 - 1) + (2x2 - 1)
= 2 (x1 + x2) - 2
= 2 () - 2
= 3 - 2
xA + xB = 1
xA . xB = (2x1 - 1) (2x2 - 1)
= 4 x1.x2 - 2(x1 + x2) + 1
= 4.(-) - 2() + 1
= -2 - 3 + 1
xA . xB = -4
Jadi persamaan kuadrat baru : x² - (xA + xB)x + xA . xB = 0
x² - x - 4 = 0
</span></span>
Answer:
Range: (-∞,∞)
Domain: (-∞,∞)
Step-by-step explanation:
Remember that if there are arrows that the function continues.
Answer:
0.15866.
Step-by-step explanation:
We have been given that on average, electricians earn approximately μ= $54,000 per year in the united states. Assume that the distribution for electricians' yearly earnings is normally distributed and that the standard deviation is σ= $12,000. We are asked to find the probability that the sample mean is greater than $66,000.
First of all, we will find the z-score corresponding to 66,000 using z-score formula.




Now, we need to find the probability that z-score is greater than 1 that is
.
Upon using formula
, we will get:

Upon using normal distribution table, we will get:


Therefore, the probability that the sample mean is greater than $66,000 would be 0.15866 or approximately
.
Answer: x = 400 MPH x+60 = 460 MPH
Step-by-step explanation:
(Distance = (Rate)(Time)
Let x = speed of the LA bound plane
Then, x+60 = speed of NYC bound plane
Sum of distances = 2464
3.4x + 2.4(x+60) = 2464
5.8x + 144 = 2464
5.8x = 2320
x = 400 MPH x+60 = 460 MPH