Answer:
125π√3/3 cm³ ≈ 226.72 cm³
Step-by-step explanation:
The length of the circular edge of the half-circle is ...
(1/2)C = (1/2)(2πr) = πr = 10π . . . . cm
This is the circumference of the circular edge of the cone, so the radius of the cone is found from ...
C = 2πr
10π = 2πr . . . . fill in the numbers; next, solve for r
r = 5 . . . . cm
The slant height of the cone is the original radius, 10 cm, so the height of the cone from base to apex is found from the Pythagorean theorem.
(10 cm)² = h² + r²
h = √((10 cm)² -(5 cm)²) = 5√3 cm
And the cone's volume is ...
V = 1/3·πr²h = (1/3)π(5 cm)²(5√3 cm)
V = 125π√3/3 cm³ ≈ 226.72 cm³
We have an arithmetic progression:
Nth=an
an=a₁+(n-1)d
a₁ is the first term.
n=number of terms.
d=common difference
10,17,24,31...
a₁=10
d=a₂-a₁=17-10=7
Therefore:
Nth=an
an=a₁+(n-1)d
an=10+(n-1)7
an=10+7n-7
an=7n+3.
Therefore: the formula for the nth is, an=a+(n-1), in this case; an=7n+3,
To check:
a₁=7*1+3=10
a₂=7*2+3=17
a₃=7*3+3=24
a₄=7*4+3=31
a₅=7*5+3=38.......
Answer:
1.95secs
Step-by-step explanation:
Given the height of the float expressed as h(t) = -16t2 - 3t + 55.
The floats reach the swimmer at h(t) = 0
Substitute
0 = -16t^2 - 3t + 55.
16t^2 + 3t - 55 = 0
Using the general formula;
t = -3±√3²-4(16)(-55)/2(16)
t = 3±√9+3520/32
t = 3±√3529/32
t = 3+59.41/32
t = 62.41/32
t = 1.95
Hence it will take 1.95secs
Answer:

Step-by-step explanation:
Given




Required
Determine the new coordinate of J
From rules of rotation,
When a point (x,y) is rotated 270 degrees CCW;
The new point becomes (y,-x)
Considering point J

This means

Where
and 
Using the above rotation rule of

The coordinates of J' becomes
