Answer:
lol how much??????.......
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:
See below.
Step-by-step explanation:
g(x) and f(4) refer to different functions.
Since we are not given f(x) is, we cannot answer the question.
Answer:
3 meters
Step-by-step explanation:
Given the scale drawing :
2m : 1m
Length of living room in real life = 6 m long
2 meter = 1 meter
Real life = scale drawing
If length = 6 meter long ;
using cross multiplication :
2 meter = 1 meter
6 meter = x
2x = 6
x = 6/2
x = 3 meter
Length of living room in drawing = 3 meters
