$I5a – 6b + 300I^{2011}$ + $(2a – 3b)^{2010}$ = 0 Tìm a,b 28/07/2021 Bởi Rylee $I5a – 6b + 300I^{2011}$ + $(2a – 3b)^{2010}$ = 0 Tìm a,b
Đáp án: \(a = – 300;b = – 200\) Giải thích các bước giải: $\begin{array}{*{20}{l}}{{{\left| {5a – 6b + 300} \right|}^{2011}} + {{\left( {2a – 3b} \right)}^{2010}} = 0}\\{{{\left| {5a – 6b + 300} \right|}^{2011}} \ge 0 \Rightarrow |5a – 6b + 300{|^{2011}} \ge 0}\\{{{\left( {2a – 3b} \right)}^{2010}} \ge 0}\\{ \Rightarrow {{\left| {5a – 6b + 300} \right|}^{2011}} + {{\left( {2a – 3b} \right)}^{2010}} \ge 0}\\{Hay\,\,{{\left| {5a – 6b + 300} \right|}^{2011}} + {{\left( {2a – 3b} \right)}^{2010}} = 0}\\{khi\left\{ {\begin{array}{*{20}{l}}{5a – 6b + 300 = 0}\\{2a – 3b = 0}\end{array}} \right.}\\{2a – 3b = 0 \Rightarrow 2a = 3b}\\{ \Rightarrow \frac{a}{3} = \frac{b}{2} = \frac{{5a – 6b}}{{3.5 – 2.6}} = \frac{{ – 300}}{3} = – 100}\\{ \Rightarrow a = – 300;b = – 200}\end{array}$ Bình luận
Đáp án:
\(a = – 300;b = – 200\)
Giải thích các bước giải:
$\begin{array}{*{20}{l}}
{{{\left| {5a – 6b + 300} \right|}^{2011}} + {{\left( {2a – 3b} \right)}^{2010}} = 0}\\
{{{\left| {5a – 6b + 300} \right|}^{2011}} \ge 0 \Rightarrow |5a – 6b + 300{|^{2011}} \ge 0}\\
{{{\left( {2a – 3b} \right)}^{2010}} \ge 0}\\
{ \Rightarrow {{\left| {5a – 6b + 300} \right|}^{2011}} + {{\left( {2a – 3b} \right)}^{2010}} \ge 0}\\
{Hay\,\,{{\left| {5a – 6b + 300} \right|}^{2011}} + {{\left( {2a – 3b} \right)}^{2010}} = 0}\\
{khi\left\{ {\begin{array}{*{20}{l}}
{5a – 6b + 300 = 0}\\
{2a – 3b = 0}
\end{array}} \right.}\\
{2a – 3b = 0 \Rightarrow 2a = 3b}\\
{ \Rightarrow \frac{a}{3} = \frac{b}{2} = \frac{{5a – 6b}}{{3.5 – 2.6}} = \frac{{ – 300}}{3} = – 100}\\
{ \Rightarrow a = – 300;b = – 200}
\end{array}$