Question

Bài toán 4: Thực hiện các phép tính sau bằng cách hợp lý.

a) (2¹⁷+ 17²).(9¹⁵– 3¹⁵).(2⁴ – 4²)

b) (8²⁰¹⁷– 8²⁰¹⁵) : (8²¹⁰⁴.8)

c) (1³+ 2³+ 3⁴ + 4⁵).(1³ + 2³ + 3³ + 4³).(3⁸ – 81²)

d) (2⁸+ 8³) : (2⁵.2³)

Answer 1

Answer 2

Answer 3

a: Ta có: \(\left(2^{17}+17^2\right)\cdot\left(9^{15}-3^{15}\right)\cdot\left(2^4-4^2\right)\)

\(=\left(2^{17}+17^2\right)\cdot\left(9^{15}-3^{15}\right)\cdot\left(16-16\right)\)

=0

b: Ta có: \(\dfrac{8^{2017}-8^{2015}}{8^{2104}\cdot8}\)

\(=\dfrac{8^{2015}\cdot\left(8^2-1\right)}{8^{2105}}\)

\(=\dfrac{1\cdot63}{8^{90}}\)+

c: Ta có: \(\left(1^3+2^3+3^4+4^5\right)\cdot\left(1^3+2^3+3^3+4^3\right)\cdot\left(3^8-81^2\right)\)

\(=\left(1^3+2^3+3^4+4^5\right)\cdot\left(1^3+2^3+3^3+4^3\right)\cdot\left(3^8-3^8\right)\)

=0

d: Ta có: \(\left(2^8+8^3\right):\left(2^5\cdot2^3\right)\)

\(=\dfrac{2^8+2^9}{2^8}\)

=3