a) 4.5²-3.2³ = 2².5²-3.2³ = 2².(5²-3.2) =2².(25-6) = 4.19 = 76

b) 28.76 + 13.28 + 9.2

= 28. (76 + 13) + 18

= 28. 89 + 18

= 2492 + 18

= 2510

c) 1024: ( 17 .2⁵+15.2⁵)

= 2¹⁰ : [2⁵.(17+15)]

= 2¹⁰: [2⁵. 32]

= 2¹⁰: [2⁵.2⁵)

= 2¹⁰:2¹⁰

= 1

a) 4.5²-3.2³

=2².5²-3.2³

=2².(25-6)

=4.11

=44
 b) 28.76+13.28+9.2

=28.(76+13)+9.2

=28.89+9.2

=2.(1246+9)

=2.1255

=2510
 c) 1024:(17.2⁵+15.2⁵)

=1024:2⁵.(17+15)

=1024:32.32

=1

a) \(26+173+74+27\)

\(=\left(26+74\right)+\left(173+27\right)\)

\(=100+200\)

\(=300\)

b) \(75\cdot37+89\cdot46+75\cdot52-89\cdot21\)

\(=75\cdot\left(37+52\right)+89\cdot\left(46-21\right)\)

\(=75\cdot89+89\cdot25\)

\(=89\cdot\left(75+25\right)\)

\(=89\cdot100\)

\(=8900\)

c) \(2^7:2^2+5^4:5^3\cdot2^4-3\cdot2^5\)

\(=2^{7-2}+5^{4-3}\cdot2^4-3\cdot2^5\)

\(=2^5+5\cdot2^4-3\cdot2^5\)

\(=2^4\cdot\left(2+5-3\cdot2\right)\)

\(=2^4\cdot\left(7-6\right)\)

\(=2^4\)

\(=16\)

d) \(100:\left\{250:\left[450-\left(4\cdot5^3-2^2\cdot25\right)\right]\right\}\)

\(=100:\left\{250:\left[450-\left(4\cdot5^3-4\cdot5^2\right)\right]\right\}\)

\(=100:\left[250:\left(450-4\cdot5^2\cdot4\right)\right]\)

\(=100:\left[250:\left(450-400\right)\right]\)

\(=100:\left(250:50\right)\)

\(=100:5\)

\(=20\)

(2x - 15)⁵ = (2x - 15)³

(2x - 15)⁵ - (2x - 15)³ = 0

(2x - 15)³.[(2x - 15)² - 1] = 0

(2x - 15)³.[(2x - 15)(2x - 15) - 1] = 0

(2x - 15)³.(4x² - 30x - 30x + 225 - 1) = 0

(2x - 15)³.(4x² - 60x + 225 - 1) = 0

(2x - 15)³.(4x² - 60x + 224) = 0

4.(2x - 15)³.(x² - 15x + 56) = 0

4.(2x - 15)³.(x² - 7x - 8x + 56) = 0

4.(2x - 15)³.[(x² - 7x) - (8x - 56)] = 0

4.(2x - 15)³.[x(x - 7) - 8(x - 7)] = 0

4.(2x - 15)³.(x - 7)(x - 8) = 0

(2x - 15)³ = 0 hoặc x - 7 = 0 hoặc x - 8 = 0

*) (2x - 15)³ = 0

2x - 15 = 0

2x = 15

x = 15/2

*) x - 7 = 0

x = 7

*) x - 8 = 0

x = 8

Vậy x = 7; x = 15/2; x = 8

1 x 99 + 3 x 97+... + 49 x 51 cứu với

a, -17

b,- 13,4

c,-68

d,700000

các bạn giải chi tiết hộ mình nhé

Lý địa đi

mk muốn đề vawb nhé bn

232/301

Gợi ý cho bn: Tách chúng ra nhé, rồi rút gọn số có ở trên cả tử và mẫu.

a)  \(3\left(4-2x\right)-2\left(x+3\right)=12-7x\)

\(\Leftrightarrow\)\(12-6x-2x-6=12-7x\)

\(\Leftrightarrow\)\(6-8x=12-7x\)

\(\Leftrightarrow\)\(x=-6\)

Vậy...

b)  \(\left|16+\right|3\left(x-2\right)||-5=20\)

\(\Leftrightarrow\)\(\left|16+\right|3\left(x-2\right)||=25\)(1)

Ta thấy:  \(\left|3\left(x-2\right)\right|\ge0\)\(\Rightarrow\)\(16+\left|3\left(x-2\right)\right|>0\)

nên từ (1)   \(\Rightarrow\)  \(16+\left|3\left(x-2\right)\right|=25\)

                   \(\Leftrightarrow\)\(\left|3\left(x-2\right)\right|=9\)

                   \(\Leftrightarrow\)  \(\orbr{\begin{cases}3\left(x-2\right)=9\\3\left(x-2\right)=-9\end{cases}}\)

                  \(\Leftrightarrow\) \(\orbr{\begin{cases}x-2=3\\x-2=-3\end{cases}}\)\(\Leftrightarrow\)\(\orbr{\begin{cases}x=5\\x=-1\end{cases}}\)

Vậy....

c)   \(\left|-5-3^2\right|-||3x+5|-7.2^3|=3^9:3^7\)

\(\Leftrightarrow\)\(14-||3x+5|-56|=9\)

\(\Leftrightarrow\)\(||3x+5|-56|=5\)

\(\Leftrightarrow\)\(\orbr{\begin{cases}\left|3x+5\right|-56=5\\\left|3x+5\right|-56=-5\end{cases}}\)

\(\Leftrightarrow\)\(\orbr{\begin{cases}\left|3x+5\right|=61\\\left|3x+5\right|=51\end{cases}}\)

đến đây bn giải tiếp nhé

a,15+ {[20/2²-5]}

15+{[20/4+5]}

15+{[5+5]}

15+{10+0}

15+10=25

b,15+{[3²-4]+2.2}

15+{[9-4]+2.2}

15+{5+2.2}

15+{5+4}

15+9=24

=24

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