Answer:
Step-by-step explanation:
Given
Required
Determine an equivalent expression
Express 81 as 
Apply law of indices
Hence:
The angle is arctan(3/4) => sin(2t) = sin(2arctan(3/4)) =
2sin(arctan(3/4))cos(arctan(3/4))
Let z = arctan(3/4) => tan(z) = 3/4
2sin(arctan(3/4))cos(arctan(3/4)) = 2sin(z)cos(z) = 2(3/5)(4/5) = 24/25
<span>cos(2t) = cos^2(t) - sin^2(t) = cos^2(z) - sin^2(z) = (4/5)^2 - (3/5)^2 = (16 - 9)/25
= 7/25
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You write each fraction that is equivalent to a whole number like this 2/1, 3/1, 4/1 as 2 over 1 or 3 over 1 or 4 over 1
Answer:
Volume = πr2h
= π×182×7
= 2268π
= 7125.1321383417 meters3
