a) (300 - 150 × 2) : (1 + 2 + 3 + ... + 2021)
= (300 - 300) : (1 + 2 + 3 + ... + 2021)
= 0 : (1 + 2 + 3 + ... + 2021)
= 0
b) (312 : 13 - 24) : (26 × 7 - 8) × 2022
= (24 - 24) : (26 × 7 - 8) × 2022
= 0 : (26 × 7 - 8) × 2022
= 0 × 2022
= 0
c) (a × 10 - 90 × a : 9) × (a × 2004 + 2013)
= (10a - 90a : 9) × (a × 2004 + 2013)
= (10a - 10a) × (a × 2004 + 2013)
= 0 × (a × 2004 + 2013)
= 0
a)
\(\text{ ( 300-150x2):(1+2+3+...+2021)}\)
= \(0:(1+2+3+...+2021)\)
= \(0\)
b)
\(\text{ (312:13-24):(26x7-8)x2022}\)
\(=0:(26x7-8)x2022\)
\(=0:174x2022\)
\(=0\)
c)
( ax10-90xa:9)x(ax2004+2013)
= ( 10a-10a) x (ax2004+2013)
= 0 x (ax2004+2013)
= 0
\(\text{a) (300 - 150 × 2) : (1 + 2 + 3 + ... + 2021)}\)
\(=\dfrac{300-300}{1+2+3+...+2021}=\dfrac{0}{1+2=3+...+2021}=0\)
\(\text{b) (312 : 13 - 24) : (26 × 7 - 8) × 2022}\)
\(\text{=(24 - 24) : (26 × 7 - 8) × 2022}\)
\(\text{= 0 : (26 × 7 - 8) × 2022}\)
\(=0\)
c)\(\text{ (a × 10 - 90 × a : 9) × (a × 2004 + 2013) }\)
\(\text{= (10a - 90a : 9) × (a × 2004 + 2013)}\)
\(\text{= (10a - 10a) × (a × 2004 + 2013) = 0 × (a × 2004 + 2013) = 0}\)