Discover answers to your questions with Westonci.ca, the leading Q&A platform that connects you with knowledgeable experts. Get detailed answers to your questions from a community of experts dedicated to providing accurate information. Experience the ease of finding precise answers to your questions from a knowledgeable community of experts.

Evaluate.

(a−2b)3 when a=−3 and b=−1/2

Enter your answer in the box.


Sagot :

Answer:

Correct option is

B

(1−3a−3b)(1+a+b)

1−2a−2b−3(a+b)

2

=−3(a+b)

2

−2(a+b)+1

=−3(a+b)

2

−3(a+b)+(a+b)+1

=−3(a+b)((a+b)+1)+((a+b)+1)

=((a+b)+1)(1−3(a+b))

=(a+b+1)(1−3a−3b)

Hi1315

Answer:

[tex]-3.5[/tex]

Step-by-step explanation:

[tex](a-2b)^{3} \\=a^{3}-6a^{2} b+6ab^{2}-8b^{3}[/tex]

Given that,

[tex]a=(-3)\\b=(-1/2)[/tex]

So,

[tex](a-2b)^{3} \\=a^{3}-6a^{2} b+6ab^{2}-8b^{3}\\=(-3)^{3}-6* (-3)^{2} *\frac{-1}{2} +6*(-3)*(\frac{-1}{2} )^{2} -8*(\frac{-1}{2} )^{3} \\= (-27)-6*9*\frac{-1}{2} +-18*\frac{1}{4} -8*\frac{-1}{8} \\=(-27)-6*-4.5-4.5+1\\=-27+27-4.5+1\\=-3.5[/tex]

Hope this helps you

Let me know if you have any other questions :-)