x.3+x.5=16
Tìm x
\(\dfrac{4x^2+16}{x^2+16}=\dfrac{3}{x^2+1}+\dfrac{5}{x^2+3}+\dfrac{7}{x^2+5}\)
Đề bài sai, pt này ko giải được
Đề đúng: \(\dfrac{4x^2+16}{x^2+6}=...\)
Mẫu số bên trái thừa mất số 1
tính theo mẫu :
Mẫu : ( 5 / 8 x 3 / 4 ) x 4 / 5 = 5 / 8 x ( 3 / 4 x 4 / 5 ) = 5 / 8 x 3 / 5 = 3 / 8
a) ( 4 / 9 x 3 / 7 ) x 7 / 4
b) ( 6 / 5 x 4 / 5 ) x 25 / 16
c) ( 7 / 8 x 16 / 9 ) x 3 / 14
a, \(\left(\frac{4}{9}.\frac{3}{7}\right).\frac{7}{4}=\frac{4}{9}\left(\frac{3}{7}.\frac{7}{4}\right)=\frac{4}{9}.\frac{3}{4}=\frac{3}{9}=\frac{1}{3}\)
b, \(\left(\frac{6}{5}.\frac{4}{5}\right).\frac{25}{16}=\frac{6}{5}\left(\frac{4}{5}.\frac{25}{16}\right)=\frac{6}{5}.\frac{5}{4}=\frac{6}{4}=\frac{3}{2}\)
c, \(\left(\frac{7}{8}.\frac{16}{9}\right).\frac{3}{14}=\frac{7}{8}\left(\frac{16}{9}.\frac{3}{14}\right)=\frac{7}{8}.\frac{8}{21}=\frac{7}{21}=\frac{1}{3}\)
a,
b,
c,
Nếu đúng thì k cho mình nhé bạn!tính theo mẫu :
Mẫu : ( 5 / 8 x 3 / 4 ) x 4 / 5 = 5 / 8 x ( 3 / 4 x 4 / 5 ) = 5 / 8 x 3 / 5 = 3 / 8
a) ( 4 / 9 x 3 / 7 ) x 7 / 4
b) ( 6 / 5 x 4 / 5 ) x 25 / 16
c) ( 7 / 8 x 16 / 9 ) x 3 / 14
( 4/9 x 3/7 ) x 7/4 = 4/9 x ( 3/7 x 7/4 ) =4/9 x 21/28 = 84/252
( 6/5 x 4/5 ) x 25/16 = ( 25/16 x 4/5 ) x 6/5 = 100/80 x 6/5 = 600/400
\(\dfrac{1}{5}\)x\(\dfrac{7}{6}\)+\(\dfrac{1}{5}\)x\(\dfrac{5}{16}\)+\(\dfrac{1}{5}\)x\(\dfrac{3}{16}\)
( 7/6 + 5/16 + 3/16) x 1/5
= ( 7/6 + 1/2) x 1/5
= ( 7/6 + 3/6) x 1/5
= 10/6 x 1/5
= 5/3 x 1/5
=1/3
1/5 x 7/6 + 1/5 x 5/16 + 1/5 x 3/16
=1/5 x (7/6 + 5/16 + 3/16)
=1/5 x (7/6 + 1/2)
=1/5 x (7/6 + 3/6)
=1/5 x 10/6
=2/6=1/3
C1:(5-|x|).(x-3)=0
C2:(x-3)+(x-2)+(x-1)+...+15+16=16
giúp vS
5(x-3) = 70 - 45 =25
x- 3 =25 : 5 = 5 x = 5 +3 =8
x= 5 + 3 = 8
b) 10 + 2 . x = 4^2 =16
2 . x = 16 - 10 = 6
x = 6 : 2 = 3
\(5\left(x-3\right)=25\)
\(x-3=25:5=5\)
\(x=5+3=8\)
\(x-3=5=5x=8\)
Hình như sai đề
\(10+2x=16\)
\(2x=6\)
\(x=3\)
mik còn k pit bn hỏi cái dj
tìm X
X - 6/5 = 3/4 : 3/16 X x 4/5 = 3/4 + 2/5
X - 6/5 = 4
X = 4 + 6/5
X= 26/5
X x 4/5 = 23/20
X = 23/20 : 4/5
X = 23/16
Tìm x biết (x-5)+(x-4)+(x-3)+...+15+16=16
Ta có: 4x=5y => x/5=y/4=>x2/25=y2/16
ta có:
x2/25=y2/16=x2-y2/25-16=1/9
x^2/25=1/9=>x^2=25/9=>x=5/3
y^2/16=1/9=>y^2=16/9=>y=4/3
tích của chúng bằng:5/3*4/3=20/9
Tính bằng cách thuận tiện nhất:
a, 3/5 + 7/12 + 5/12
b, 4/26 + 2/5 x 26
c, 5/7 x 9/16 + 7/16 x 5/7
3/5+7/12+5/12
=3/5+(7/12+5/12)
=3/5+1
=8/5
a.3/5+1=8/5
b.4/26+52/5=686/65
c.(9/16+7/16)*5/7=1*5/7=5/7