rut gon A= 2 + 2 mu 2 + 2 mu 3 + 2 mu 4 +....+ 2 mu 8
cac bn giup mk nka
rut gon a=4 mu 5. 9 mu 4 - 2 . 6mu 9/2 mu 10. 3 mu 8+ 6mu 8 .20
Rut gon cac phan so
a) -21 / 49 ; 39 / -65
b ) 5 mu 4 . 7 mu 3 / 5 mu 5 . 7 mu 2 ; 2 mu 2 . 3 mu 5 . 5 / 2 mu 4 . 3 mu 4 . 5 mu 2
a)=-3/7
=-3/5
b)=625
=343
=3125
=49
c)=4
=243x5=1215
=16x81x25=32400
rut gon
A = 1 +1 /2 +1/2 mu 2+ 1/2 mu 3 .+...... + 1/2 mu 2012
B1) Tinh
a) 245-4 . [15: 8 +2.(4+3 mu 2 -9)]
b) 375: 5 mu 3 -( 3 mu 8: 3 mu 6 -2 .2 mu 3)
B2: Tim x
a) 2x -2 mu 3 .3 mu 2=138
b) ( 6x- 3 mu 4) . 7 mu 3= 3 . 7 mu 4
c) 1+2+3+..............+x =500500
nho cac ban giup minh nhe
1.tim x thuoc N biet:
a)(2x+1)mu 3=125 b)(x-5)mu 4=(x-5)mu 6 c)2 mu x-15=17 d)(7x-11)mu 3=2 mu 5. 5mu 2+200
2.viet cac tich sau hoac thuong duoi dang luy thua cua mot so:
a)2 mu 5 . 8 mu 4 b)25.125 c)25 mu 5:25 mu 7
3.viet cac tich, thuong sau duoi dang luy thua:
a) 2 mu 10:8 mu 3 b)12 mu 7:6 mu 7 c)5 mu 8:25 mu 2
4.tinh gia tri cac bieu thuc sau:
a mu3 . a mu 9 (a mu 5)mu7 (a mu 6)mu 4. a mu 12 4.5 mu 2-2.3 mu 2
Bài 1 :
a) (2x + 1)3 = 125
=> (2x + 1)3 = 53
=> 2x + 1 = 5
=> 2x = 5 - 1
=> 2x = 4
=> x = 2
b) (x - 5)4 = (x - 5)6
Với hai mũ khác nhau , ta chỉ có thể tìm được giá trị biểu thức bằng 1 hoặc 0 (giá trị của chúng bằng nhau)
+) (x - 5)4 = (x - 5)6 = 0
=> (x - 5)4 = 0
=> (x - 5)4 = 04
=> x - 5 = 0 => x = 0 + 5 = 5
+) (x - 5)4 = (x- 5)6 = 1
=> (x - 5)4 = 1
=> (x - 5)4 = 14
=> x - 5 = 1
=> x = 1 + 5
=> x = 6
Bài 4 :
a3 . a9 = a3 + 9 = a12
(a5)7.(a6)4 .a12 = a35 . a24 . a12 = a35 + 24 + 12 = a71
4.52 - 2.32 = 4.25 - 2.9
= 100 - 18
= 82
mong cac ban giup, minh can gap lam,tuy minh trinh bay hoi xau nhung mong cac ban giup
3.viet cac tich, thuong sau duoi dang luy thua:
a) \(\dfrac{2^{10}}{8^3}\)
\(=\dfrac{2^{10}}{\left(2^3\right)^3}\)
\(=\dfrac{2^{10}}{2^9}\)
\(=2^1\)
rut gon mo ngoac don 1 tru can 2 tat ca mu 2
( x - 1 ) mu 2 : 5 mu 21 = 25 mu 30 . 5
2.3 mu x + 1 = 10.3 mu 12 + 8 : 27 mu 4
( 19x + 2 .5 mu 2) : 14 = ( 13 - 8 ) mu 2
1351 - 2 . ( x + 3) = 4 mu 12 : 8 mu 7 + 3
mong m.n giup mk vs !!!!
(x-1)^2:5^21=25^30.5
(x-1)^2=25^30.5.5^21
=(5^2)^30.5^22
= 5^60.5^22
(x-1)^2 =5^82
(x-1)^2=(5^41)^2
x-1=5^41
x=5^41+1
2.3^x+1=10.3^12+8:3^12
2.3^x+1=10+8=18
3^x+1=18/2=9
3^x+1=3^2
x+1=2
x=1
bai 2, viet gon duoi dang 1 luy thua ;
a, 3 mu 6 nhan 3 mu 8 b, 2 mu 7 nhan 2 mu 11 c 5 mu 4 nhan 5 mu 6 d,16 nhan 2 mu 5
e, 3 mu 7 nhan 2 mu 7 f, 25 nhan 5 mu 7 nhan 125 g, 27 nhan 3 mu 4 nhan 9 h, 64 nhan 8 nhan 2 mu5
giup minh voi thu 6 la minh can roi ai nhanh minh nhan like
tính tổng
B= 7-7 mu 4 + 7 mu 4 -........+7 mu 301
A = 1 + 5 mũ 2 + 5 mu 4 + 5 mu 6 +.....+5 mu 200
tính
A= 1/7+1/7mu 2 + 1/7 mu 3+......+1/7mu 100
B=-4/5+4/5 mu 2 - 4/5 mu 3 + ....+4/5mu 200
tính A=25 mũ 8 + 25 mũ 4 + 25 mu 20 +......+25 mu 4 +1 / 25 mu 20 + 25 mu 28 + 25 mu 26 +.....= 25 mu 2 +1
7 × 3 mu x + 20 × 3 mu x = 3 mu 25