Answer:
-30
Step-by-step explanation:
Tn = a1 + (n-1)d = 34 + (-2)(n-1) = 34-2n+2 = 36-2n
hence,
10= 36-2n
2n = 36
n = 13
20 terms from the last term would be 13+20 = 33
T33 = 36-2(33) = -30
2km=2 kilometer
kilo=1000 so 2 km=2000m
25m
2500cm
cm=centimeter=1/100 of a meter
so
2500cm=25m
mm=milimeter=1/1000 meter
so
3000mm=3m
so the longets is obviously 2000m or 2km
Answer:
DA/dt = 75.27 cm²
Step-by-step explanation:
Cube Volume = V(c) = 683 cm³
DV(c) /dt = 824 cm³
V(c,x) = x³
Then
DV(c,x)/ dt = 3x² Dx/dt
( DV(c,x)/ dt )/ 3x² = Dx/dt (1)
Now as V(c,x) = x³ when V(c,x) = 683 cm³ x = ∛683
x = 8.806 ( from excel)
And by subtitution of this value in equation (1)
Dx/dt = ( DV(c,x)/ dt )/ 3x² ⇒ Dx/dt = 824 / 3*x²
Dx/dt = 824 /3*77.55
Dx/dt = 824/232,64
Dx/dt = 3,542
Then we got Dx/dt where x is cube edge. The area of the face is x² then
the rate of change of the suface area is
DA/dt = ( Dx/dt )²*6 ( 6 faces of a cube)
DA/dt = (3.542)²*6
DA/dt = 75.27 cm²
