Giải phương trình :
a, x/2017 + x - 1/2018 = x - 2/2019 - 1
b, ( 2x + 1 ) + ( 4x + 3 ) + ( 6x + 5 ) +...+ ( 100x + 99 ) = 7600
c, ( x + 1 ) + ( 2x + 5 ) + ( 3x + 9 ) +...+ ( nx + 101 ) = 975
d, ( x - 1 ) + ( 2x - 3 ) + ( 3x - 5 ) +...+ ( nx - 2019 ) = n
Giải giúp mình nha, cảm ơn nhìu ❤
b. \(\left(2x+1\right)+\left(4x+3\right)+\left(6x+5\right)+...+\left(100x+99\right)=7600\)
\(\rightarrow\left(2x+4x+6x+...+100x\right)+\left(1+3+5+...+99\right)=7600\)
\(\rightarrow\frac{\left(2x+100x\right).50}{2}+\frac{\left(1+99\right).50}{2}=7600\)
\(\rightarrow51x.50+50.50=7600\)
\(\rightarrow51x.50+2500=7600\)
\(\rightarrow51x.50=7600-2500\)
\(\rightarrow51x.50=5100\)
\(\rightarrow50x=100\)
\(\rightarrow x=\frac{100}{50}=2\)
Vậy x = 2