First term ,a=4 , common difference =4-7=-3, n =50
sum of first 50terms= (50/2)[2×4+(50-1)(-3)]
=25×[8+49]×-3
=25×57×-3
=25× -171
= -42925
derivation of the formula for the sum of n terms
Progression, S
S=a1+a2+a3+a4+...+an
S=a1+(a1+d)+(a1+2d)+(a1+3d)+...+[a1+(n−1)d] → Equation (1)
S=an+an−1+an−2+an−3+...+a1
S=an+(an−d)+(an−2d)+(an−3d)+...+[an−(n−1)d] → Equation (2)
Add Equations (1) and (2)
2S=(a1+an)+(a1+an)+(a1+an)+(a1+an)+...+(a1+an)
2S=n(a1+an)
S=n/2(a1+an)
Substitute an = a1 + (n - 1)d to the above equation, we have
S=n/2{a1+[a1+(n−1)d]}
S=n/2[2a1+(n−1)d]
Answer:
How can you reduce the variability of a statistic? By taking a larger sample. Larger samples give smaller spread. Also by better design, such as stratified sampling. What effect does the size of the population have on the variability (spread) of a statistic?
Step-by-step explanation:
Answer:
The parameters in the parent function are:
- the parameter correspondig to - 3 in the given function is 0 in the parent function.
- the parameter corresponding to 1/2 in the given function is 1 in the parent function, and
- the parameter corresponding to - 1 in the given function is 1 in the parent function.
Explanation:
The given function is 
.
The parent function of 
. The parameters of the given function are -1 (which is mutlyplying the value of cosine, 1/2 which is multiplying the argument (x), and - 3 which is subtracted.
In the parent function, those values are 1, 1, and 0.
It may help you representing the parameters in the given function with letters:
Then, in the given function A = - 1, B = 1/2, and C = -3.
Now, you can write the parent function:
Then, the parameters are A = - 1, B = 1, and C = 0.
Answer:
Step-by-step explanation:
x-5/2=-6
2(x-5)=-6x2
2x-10=-12
2x=-12+10
2x=-2
X=-1
There are three terms in this polynomial, making it a trinomial. The terms are "abcd", "e", and "h^2".
