Answer:
2.42
Step-by-step explanation:
standard deviation= sqrt(variance)
Variance=E[X2] - E[X]2
E[X] = sum(X)/n=35/9, so E[X]2 = 1225/81
E[X2] =sum(X2)/n = 189/9 = 170/81
Variance= 476/81
Standard deviation = sqrt(476/81) ~2.42
Answer:
x= -1/2 = -0.500
x=4
Step-by-step explanation:
2x^2-7x-4=0
2x^2-8x+1x-4=0
2x(x-4)+1(x-4)=0
(2x+1)(x-4)=0
2x+1=0...2x= -1.. x= -1/2 x-4=0 .. x=4
checking the solution
2(-1/2)^2-7(-1/2)=4..... 4=4
2(4)^2-7(4)=4....... 4=4
This is one of the easiest ways to get the answer
Answer:
The graph of the function 
is attached as image below.
Analysis:
We have two intersection points in the graph
The function intersects the y-axis at points (0,4)
The function intersects the x-axis at points (-16,0)
f(x) is positive for x>-`16
f(x) is negative for x<-`16
