Answer:
a_n = 28-2n
Step-by-step explanation:
Given sequence is:
26,24,22,20
We can see that the difference between consecutive terms is same so the sequence is an arithmetic sequence
The standard formula for arithmetic sequence is:
Here,
a_n is the nth term
a_1 is the first term
and d is the common difference
So,
d = 24-26
= -2
a_1 = 26
Putting the values of d and a_1
Hence, the recursive formula for given sequence is: a_n = 28-2n ..
Answer:
The width of member is as follows:
b = 3 ft
b = 3 × 12 in.
b= 36 in.
The depth of member is as follows:
d = 8 ft
d = 8 × 12 in.
d=96 in.
Since the structure used is Douglas fir-Larch lumber of size 3 × 8 size. Hence, tensile strength, f =1000 psi
Calculate the net area of the member as follows:
A = (b - ∅) × d
A= (36 - 7/8) × 96
Calculate the maximum axial tensile load by ASD method as follows:
P = f × A
P = 1000 x 3372
P = 3372000 lbs
P = 3372 kips