Recall the definition of the cross product with respect to the unit vectors:
i × i = j × j = k × k = 0
i × j = k
j × k = i
k × i = j
and that the product is anticommutative, so that for any two vectors u and v, we have u × v = - (v × u). (This essentially takes care of part (b).)
Now, given a = 8i + j - 2k and b = 5i - 3j + k, we have
a × b = (8i + j - 2k) × (5i - 3j + k)
a × b = 40 (i × i) + 5 (j × i) - 10 (k × i)
… … … … - 24 (i × j) - 3 (j × j) + 6 (k × j)
… … … … + 8 (i × k) + (j × k) - 2 (k × k)
a × b = - 5 (i × j) - 10 (k × i) - 24 (i × j) - 6 (j × k) - 8 (k × i) + (j × k)
a × b = - 5k - 10j - 24k - 6i - 8j + i
a × b = -5i - 18j - 29k
Answer:
it helps with balance and speed.
"The football shoes have spikes or studs because the studs or spikes provides larger frictional force than normal shoes while running on the grass. The studs prevents player from slipping on the grass and help to run faster and change direction quickly without slipping"
It would be funny because . I will not be good
Explanation:
Given that,
Size of object, h = 0.066 m
Object distance from the lens, u = 0.210 m (negative)
Focal length of the converging lens, f = 0.14 m
If v is the image distance from the lens, we can find it using lens formula as follows :
(a) Magnification,

(b) Magnification, 
h' is image height

Hence, this is the required solution.
The period of the pendulum is given by the following equation
T = 2π * sqrt (L/g)
Where g is the gravity (free fall acceleration)
L is the longitude of the pendulum
T is the period.
We find g.............> (T /2π)^2 = L/g
g = L/(T /2π)^2...........> g = 22.657 m/s^2