a) 95 + 11 x 206

= 95 + 2266 = 2361

b) 95 x 11 + 206

= 1045 + 206 = 1251

c) 95 x 11 x 206

= 1045 x 206 = 215270

95 x 107 - 95 x ... = 9500

95 x 107 - 95 x ... = 95 x 100

95 x 107 - 95 x 100 = 95 x ...

95 x 7  =   95 x 7 

95 x 107 - 95 x ... = 9500

=> 95 x 107 - 95 x 7 = 9500

Ta có: \(\dfrac{95}{x}+\dfrac{95}{x+1}=5\)

\(\Leftrightarrow5x\left(x+1\right)=95x+95+95x\)

\(\Leftrightarrow5x^2+5x-190x-95=0\)

\(\Leftrightarrow5x^2-185x-95=0\)

\(\Leftrightarrow x^2-37x-19=0\)

\(\Delta=\left(-37\right)^2-4\cdot1\cdot\left(-19\right)=1445\)

Phương trình có hai nghiệm phân biệt là:

\(\left\{{}\begin{matrix}x_1=\dfrac{37-17\sqrt{5}}{2}\\x_2=\dfrac{37+17\sqrt{5}}{2}\end{matrix}\right.\)

\(\dfrac{95}{x}+\dfrac{95}{x+1}=5\)

<=> \(\dfrac{95\left(x+1\right)}{x\left(x+1\right)}+\dfrac{95x}{x\left(x+1\right)}=\dfrac{5x\left(x+1\right)}{x\left(x+1\right)}\)

=> 95x + 95 + 95x = 5x² + 5x

<=> 190x - 5x - 5x² = -95

<=> -5x² + 185x + 95 = 0

<=> x = 37,5

ĐK x >=0. Đặt \(\sqrt{x}\) = t>=0. ta có PT: \(t^4\)+ \(t^2\) - 5 = 0.

Đặt y = \(t^2\)>=0 suy ra \(y^2\)+ y - 5 = 0.Giải PT y = ( - 1 + \(\sqrt{21}\))/2 (loại nghiệm âm).

suy ra \(t^2\) = (10 - \(\sqrt{21}\))/2.Giải tương tự tìm x

\(\Leftrightarrow\left(\dfrac{x-1}{99}-1\right)+\left(\dfrac{x-99}{1}-1\right)+\left(\dfrac{x-3}{97}-1\right)+\left(\dfrac{x-97}{3}-1\right)+\left(\dfrac{x-5}{95}-1\right)+\left(\dfrac{x-95}{5}-1\right)=0\)

=>x-100=0

=>x=100

=15*(95+5)-95

=15*100-95

=1500-95

=1405

15 x 95+15 x 5-95

=15 x 95+15 x 5-15 x 9

=15 x(95+5-9)

=15 x (100-9)

=15 x100-15 x 9

=1500-95

=1405

=15*(95+5)-95

=15*100-95

=1500-95

=1405