K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

a: \(A=x^2-10x+25+1\)

\(=\left(x-5\right)^2+1\)

\(=100^2+1=10001\)

b: \(B=2\left(a^2+a-5a-5\right)-\left(a^2-10a+25\right)+36\)

\(=2a^2-8a-10-a^2+10a-25+36\)

\(=a^2+2a+1\)

\(=\left(a+1\right)^2=100^2=10000\)

c: \(C=a^3+3a^2+3a+1=\left(a+1\right)^3=100^3=1000000\)

d: \(E=a^3+3a^2+3a+1+5\)

\(=\left(a+1\right)^3+5\)

\(=30^3+5=27005\)

a: \(=3x+5-3x+\dfrac{5}{3}-3x-1=3x+\dfrac{17}{3}\)

b: \(=\left(3a+2-3a+2\right)^2=4^2=16\)

1. \(4x^2-17xy+13y^2=4x^2-4xy-13xy+13y^2=4x\left(x-y\right)-13y\left(x-y\right)=\left(x-y\right)\left(4x-13y\right)\)

2. \(2x\left(x-5\right)-x\left(3+2x\right)=26\Leftrightarrow2x^2-10x-3x-2x^2=26\Leftrightarrow-13x=26\Leftrightarrow x=-2\)

3. \(A=\left(2a-3b\right)^2+2\left(2a-3b\right)\left(3a-2b\right)+\left(2b-3a\right)^2\)

\(\Leftrightarrow\left(2a-3b\right)^2-2\left(2a-3b\right)\left(2b-3a\right)+\left(2b-3a\right)^2=\left(2a-3b-2b+3a\right)^2=\left(5a-5b\right)^2\)

\(=25\left(a-b\right)^2=25\cdot100=2500\)

4 tháng 1 2017

a/ đk: a\(\ne b\), b\(\ne0,a\ne-b\)

= \(\frac{a\left(a-b\right)-a^2-b^2}{a-b}.\frac{a+b+2b}{b\left(a+b\right)}\)

= \(\frac{a^2-ab-a^2-b^2}{a-b}.\frac{a+3b}{b\left(a+b\right)}\)

= \(\frac{-ab-b^2}{a-b}.\frac{a+3b}{b\left(a+b\right)}\)

= \(\frac{-b\left(a+b\right)\left(a+3b\right)}{b\left(a+b\right)\left(a-b\right)}\)

= \(\frac{-a-3b}{a-b}\)

b/ đk: a\(\ne0,a\ne\pm3\)

= \(\left[\frac{3a+1}{a\left(a-3\right)}+\frac{3a-1}{a\left(a+3\right)}\right].\frac{\left(a-3\right)\left(a+3\right)}{a^2+1}\)

= \(\frac{\left(3a+1\right)\left(a+3\right)+\left(3a-1\right)\left(a-3\right)}{a\left(a-3\right)\left(a+3\right)}.\frac{\left(a-3\right)\left(a+3\right)}{a^2+1}\)

= \(\frac{6a^2+6}{a\left(a-3\right)\left(a+3\right)}.\frac{\left(a-3\right)\left(a+3\right)}{a^2+1}\)

= \(\frac{6\left(a^2+1\right)\left(a-3\right)\left(a+3\right)}{a\left(a^2+1\right)\left(a-3\right)\left(a+3\right)}\)

= \(\frac{6}{a}\)