if 3x+1/3x=3,find: (1) 9x^2+1/9x^2. (2)27x^3+1/27x^3
Answers
Answered by
0
If 3x + 1/2x = 5, then what is the value of 8x^3 + 1/27x^3?
Answer
4
Follow
Request
More
Promoted by NRFA
Making pregnancy possible.
The road through infertility can be a costly one. Discover a new way with embryo adoption on NRFA.org.
Learn More
6 ANSWERS

Badarinath Hs, Ph.D. in Civil Engineering. Maths keeps one mentally active.
Answered Dec 11
3x + 1/2x = 5, or
6x^2 -10x + 1 = 0
x1 = [10 +(100–24)^0.5]/12
= [10 +76^0.5]/12
= [10 +8.717797887]/12 = 1.559816491
x1^3 = 1.559816491^3 = 3.795076395
x2 = [10 -(100–24)^0.5]/12
= [10 -76^0.5]/12
= [10 -8.717797887]/12 = 0.106850176
x2^3 = 0.106850176^3 = 0.0012199042
Hence 8*x1^3 + 1/27*x1^3
= 8*3.795076395 + /27*3.795076395 = 30.36061116 + 0.00975923359 = 30.37037039
8*x2^3 + 1/27*x2^3
= 8*0.0012199042 + /27*0.0012199042 = 0.00975923359 + 30.36061116 = 30.37037039
Answer = 30.37037039
Answer
4
Follow
Request
More
Promoted by NRFA
Making pregnancy possible.
The road through infertility can be a costly one. Discover a new way with embryo adoption on NRFA.org.
Learn More
6 ANSWERS

Badarinath Hs, Ph.D. in Civil Engineering. Maths keeps one mentally active.
Answered Dec 11
3x + 1/2x = 5, or
6x^2 -10x + 1 = 0
x1 = [10 +(100–24)^0.5]/12
= [10 +76^0.5]/12
= [10 +8.717797887]/12 = 1.559816491
x1^3 = 1.559816491^3 = 3.795076395
x2 = [10 -(100–24)^0.5]/12
= [10 -76^0.5]/12
= [10 -8.717797887]/12 = 0.106850176
x2^3 = 0.106850176^3 = 0.0012199042
Hence 8*x1^3 + 1/27*x1^3
= 8*3.795076395 + /27*3.795076395 = 30.36061116 + 0.00975923359 = 30.37037039
8*x2^3 + 1/27*x2^3
= 8*0.0012199042 + /27*0.0012199042 = 0.00975923359 + 30.36061116 = 30.37037039
Answer = 30.37037039
smritikumari:
i don't think this is the answer to my question
Similar questions