Answer:
First Term = 6
Common Ratio = 3
Step-by-step explanation:
According to the Question,
Given, The sum of the first eight terms in a Geometric Series is 19680 and the sum of the first four terms is 240 .Thus, [tex]S_{8} = 19680[/tex] & [tex]S_{4} = 240[/tex] .
The Sum of n-term of Geometric Mean is [tex]S_{n} = \frac{a(r^{n-1)} }{r-1}[/tex] Where, r>1 , a=First term of G.P & r=common Ratio .Now, on solving [tex]\frac{S_{8} }{S_{4} }[/tex] we get,
[tex]\frac{19680}{240} = \frac{\frac{a(r^{8-1)} }{r-1}}{\frac{a(r^{4-1)} }{r-1}}[/tex]
[tex]82 = \frac{r^{8}-1 }{r^{4}-1 }[/tex]
[tex]82r^{4}-82 = r^{8}-1\\r^{8}-82r^{4}+81 = 0\\r^{8}-81r^{4}-r^{4}+81 = 0\\(r^{4}-81)( r^{4}-1) =0[/tex](r=1 is not possible so neglect [tex]( r^{4}-1) =0[/tex] )
So, r=3 Now Put this value in [tex]S_{4} = {\frac{a(r^{4-1)} }{r-1}}[/tex] We get a=6 .
Please help me!! Perimeter: about ______ ft squared
Area: about ________ ft squared
Answer:
55.1 ft ; 236.7 ft^2
Step-by-step explanation:
radius = 7.5 ft
Perimeter of the semicircles = 2 * radius * pi = 2 * 7.5 * pi = 47,12389 ft
Perimeter of the rectangle = 4 * 2 = 8 ft
Total perimeter = 55,12389 ft
Area of the semicircles = radius^2 * pi = 7.5^2 * pi = 176,714587 ft^2
Area of the rectangle = 4 * 15 = 60 ft^2
Total area = 236,714587 ft^2
WILL MARK BRANLIEST
When describing a rotation, what
information must you include?
Answer:
The point you are rotating at (also called the centre of rotation)
The angle of rotation (usually in degrees but I don't know your school)
Direction of the turn
Step-by-step explanation:
state wether the product of √3 and √9 is rational or irrational. explain your answer
√9 is rational and √3 irrational number
