MHB How do I factor this expression: 3(x + 5)^3 + 2(x + 5)^2?

  • Thread starter Thread starter mathdad
  • Start date Start date
  • Tags Tags
    Polynomial
AI Thread Summary
The expression 3(x + 5)^3 + 2(x + 5)^2 can be factored as (x + 5)^2[3(x + 5) + 2], which simplifies to (x + 5)^2[3x + 17]. This factoring method is confirmed as correct by participants in the discussion. Additional factoring questions from the same textbook section will be shared in the future. The focus remains on understanding the steps involved in factoring expressions in precalculus.
mathdad
Messages
1,280
Reaction score
0
Precalculus by David Cohen, 3rd Edition
Chapter 1, Section 1.3.
Question 46a.

Factor the expression.

3(x + 5)^3 + 2(x + 5)^2

(x + 5)^2[3(x + 5) + 2]

(x + 5)^2[3x + 15 + 2]

(x + 5)^2[3x + 17]

Correct?
 
Mathematics news on Phys.org
RTCNTC said:
Precalculus by David Cohen, 3rd Edition
Chapter 1, Section 1.3.
Question 46a.

Factor the expression.

3(x + 5)^3 + 2(x + 5)^2

(x + 5)^2[3(x + 5) + 2]

(x + 5)^2[3x + 15 + 2]

(x + 5)^2[3x + 17]

Correct?

yes
 
Looks good to me. :D
 
There are a few more factoring questions from section 1.3 that will be posted in the coming days as I travel from chapter to chapter and section to section in the precalculus textbook, 3rd edition by David Cohen.
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
Thread 'Imaginary Pythagoras'
I posted this in the Lame Math thread, but it's got me thinking. Is there any validity to this? Or is it really just a mathematical trick? Naively, I see that i2 + plus 12 does equal zero2. But does this have a meaning? I know one can treat the imaginary number line as just another axis like the reals, but does that mean this does represent a triangle in the complex plane with a hypotenuse of length zero? Ibix offered a rendering of the diagram using what I assume is matrix* notation...
Fermat's Last Theorem has long been one of the most famous mathematical problems, and is now one of the most famous theorems. It simply states that the equation $$ a^n+b^n=c^n $$ has no solutions with positive integers if ##n>2.## It was named after Pierre de Fermat (1607-1665). The problem itself stems from the book Arithmetica by Diophantus of Alexandria. It gained popularity because Fermat noted in his copy "Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos, et...

Similar threads

Back
Top