(3x – 2^4). 7 ^ 3 = 2 . 7^4 x – [ 42 + (-28)] = -8 Ix-3I=I5I + I-7I g) 4- ( 7 – x) = x – (13-4) 07/12/2021 Bởi Jade (3x – 2^4). 7 ^ 3 = 2 . 7^4 x – [ 42 + (-28)] = -8 Ix-3I=I5I + I-7I g) 4- ( 7 – x) = x – (13-4)
1/ (3x- 2^4). 7³=2. 7^4 (3x- 16). 343= 4802 3x- 16=4802 :343= 14 3x= 14+16=30 x= 30: 3=10 2/ x-[42+(-28)]=-8 x-14=-8 x=(-8)+14 x=6 3/ |x-3|=|5|+|-7| |x-3|=5+7=12 x-3=±12 TH1: TH2: x-3=12 x-3=-12 x=12+3=15 x=(-12)+3=-11 Vậy x∈ {15; -11} 4/ 4-(7-x)=x-(13-4) 4-7+x=x-9 (-3)+x=x-9 2x=3+9 2x=12 x=12:2 x=6 Bình luận
1/ (3x- 2^4). 7³=2. 7^4
(3x- 16). 343= 4802
3x- 16=4802 :343= 14
3x= 14+16=30
x= 30: 3=10
2/ x-[42+(-28)]=-8
x-14=-8
x=(-8)+14
x=6
3/ |x-3|=|5|+|-7|
|x-3|=5+7=12
x-3=±12
TH1: TH2:
x-3=12 x-3=-12
x=12+3=15 x=(-12)+3=-11
Vậy x∈ {15; -11}
4/ 4-(7-x)=x-(13-4)
4-7+x=x-9
(-3)+x=x-9
2x=3+9
2x=12
x=12:2
x=6