Tính nhanh
942x112-942x11-942
1/3x14/15+14/15x2/3
cần gấp
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Vì x=14 nên x+1=15
Thay 15=x+1 vào A(x) Ta có:
A(x)= x^15-(x+1)x^14+(x+1)x^13-(x+1)x^12+...+(x+1)x^3-(X+1)^2+(x+1)x-15
=x^15-x^15-x^14+x^14+x^13-x^13-...+X^4+x^3-X^3-x^2+x^2-x-15
=x-15
=> A(14)=14-15=-1
Vậy A(14)=-1
k mình nha
\(y:2+y.0,75=15,34-14,09\)
\(y.0,5+y.0,75=1,25\)
\(y.\left(0,5+0,75\right)=1,25\)
\(y.1,25=1,25\)
\(y=1\)
Chú ý:Dấu \(.\) là dấu nhân nha.
a) \(\left(-15\right)\cdot\left(10-12\right)=\left[\left(-15\right)\cdot10-\left(-15\right)\cdot12\right]=-150+180=30\)
b) \(\left(-17\right)\cdot10-\left(-3\right)\cdot10=\left[-17-\left(-3\right)\right]\cdot10=\left(-17+3\right)\cdot10=-14\cdot10=-140\)
a) \(\frac{3}{5}:\left(-\frac{1}{15}-\frac{1}{6}\right)+\frac{3}{5}:\left(-\frac{1}{3}-1\frac{1}{15}\right)\)
\(=\frac{3}{5}:\left(-\frac{1}{15}-\frac{1}{6}-\frac{2}{6}-1+\frac{1}{15}\right)\)
\(=\frac{3}{5}:\left(-\frac{1}{2}-1\right)\)
\(=\frac{3}{5}:\left(-\frac{3}{2}\right)\)
\(=-\frac{2}{5}\)
b) \(\left(-\frac{3}{4}+\frac{5}{13}\right):\frac{2}{7}-\left(2\frac{1}{4}+\frac{8}{13}\right):\frac{2}{7}\)
\(=\left(-\frac{3}{4}+\frac{5}{13}-2+\frac{1}{4}+\frac{8}{13}\right):\frac{2}{7}\)
\(=\left(-\frac{1}{2}+1-2\right):\frac{2}{7}\)
\(=\left(-\frac{1}{2}-1\right):\frac{2}{7}\)
\(=-\frac{3}{2}:\frac{2}{7}\)
\(=-\frac{21}{4}\)
B=2^10*(2*3)^15+3^14*3*5*(2^2)^13/2^19*(2*3^2)^7*3-3^15*2^25
B=2^10*2^15*3^15+3^15+3^15*5*2^26/2^19*2^7*3^14**3-3^15*2^25
B=2^25*3^15+5*2*3^15*2^25/2*2^25*3^15-3^15*2^25
B=1*2^25*3^15+10*2^25*3^15/2*2^25*3^15-2^25*3^15
B=2^25*3^15*(1+10)/2^25*3^15*(2-1)=11/1=11
\(942\times112-942\times11-942\)
\(=942\times\left(112-11-1\right)\)
\(=942\times100\)
\(=94200\)
\(\dfrac{1}{3}\times\dfrac{14}{15}+\dfrac{14}{15}\times\dfrac{2}{3}\)
\(=\dfrac{14}{15}\times\left(\dfrac{1}{3}+\dfrac{2}{3}\right)\)
\(=\dfrac{14}{15}\times\left(\dfrac{1+2}{3}\right)\)
\(=\dfrac{14}{15}\times\dfrac{3}{3}\)
\(=\dfrac{14}{15}\times1\)
\(=\dfrac{14}{15}\)
942 \(\times\) 112 - 942 \(\times\) 11 - 942
= 942 \(\times\) 112 - 942 \(\times\) 11 - 942 \(\times\) 1
= 942 \(\times\) ( 112 - 11 - 1)
= 942 \(\times\) 100
= 94200