X^2 - 8x-9=0
D = b^2- 4*a*c = 64- 4* (-9) = 64+36=100 =10^2
X1 = (8-10)/2 = -1
X2= (8+10)/2= 9
Answer: Lattice parameter, a = (4R)/(√3)
Step-by-step explanation:
The typical arrangement of atoms in a unit cell of BCC is shown in the first attachment.
The second attachment shows how to obtain the value of the diagonal of the base of the unit cell.
If the diagonal of the base of the unit cell = x
(a^2) + (a^2) = (x^2)
x = a(√2)
Then, diagonal across the unit cell (a cube) makes a right angled triangle with one side of the unit cell & the diagonal on the base of the unit cell.
Let the diagonal across the cube be y
Pythagoras theorem,
(a^2) + ((a(√2))^2) = (y^2)
(a^2) + 2(a^2) = (y^2) = 3(a^2)
y = a√3
But the diagonal through the cube = 4R (evident from the image in the first attachment)
y = 4R = a√3
a = (4R)/(√3)
QED!!!
90/2 = 45
45/1700 = 0.02647
0.02647 x 100 = 2.64
2.46%
Answer:
45
Step-by-step explanation:
Given that the number of savory dishes is 9 and the number of sweet dished is 5.
Denoting all the 9 savory dishes by
, and all the sweet dishes by
.
The possible different mix-and-match plates consisting of two savory dishes are as follows:
There are 9 plates with
from sweet plates which are 
There are 9 plates with
from sweet plates which are 
Similarly, there are 9 plated for each
and 
Hence, the total number of the different mix-and-match plates consisting of two savory dishes
