Answer:
see explanation
Step-by-step explanation:
Using De Moivre's theorem
Given
[ 4(cos15° + isin15° ) ]³, then
= 4³ [ cos(3 × 15°) + isin(3 × 15°) ]
= 64 (cos45° + isin45° )
= 64 (
+
i )
= 64 (
(1 + i) )
= 32
(1 + i)
= 32
+ 32
i
(7+11) is 18, (8/2) is 4, 18-4 is 14! If this expression is 6 less than her age, she would be 20!
Answer:
The Distance cover by boat in 2 hours and 15 minutes is 72 km
Step-by-step explanation:
Given as :
The Distance cover by boat = 128 kilometer
The time taken is 4 hours
As , Distance = Speed ×Time
So , Speed = 
Or, Speed = 
∴ Speed = 32 km per hour
Now, again The boat travel 2 hours and 15 minutes further with speed 32 kmph
So, Time2 = 2 +
Or, Time2 = 2 +
I.e Time2 =
hours
Again , Distance = Speed ×Time
So , Distance = 32kmph ×
hours
I.e Distance =
= 72 kilometer
Hence The Distance cover by boat in 2 hours and 15 minutes is 72 km Answer