Bài 1) Tính nanh nếu có thể
1) \(63^2-47^2\)
2) \(127^2+146.127+73^2\)
3) \(215^2-105^2\)
4) \(\left(4+1\right).\left(4^2+1\right).\left(4^4+1\right).\left(4^6+1\right)...\left(4^{156}+1\right)\)
5) \(2\frac{1}{315}.\frac{3}{651}-\frac{3}{105}.3\frac{650}{651}-\frac{4}{315.651}+\frac{4}{105}\)
6) \(444443.444448.444441-444445.4444440.444447\)
1) \(63^2-47^2=\left(63+47\right)\left(63-47\right)=110.16=1760\)
2) \(127^2+146.127+73^2=\left(127+73\right)^2=200^2=40000\)
3) \(215^2-105^2=\left(215-105\right)\left(215+105\right)=110.320=35200\)
4) mk chỉnh lại đề:
\(\left(4+1\right)\left(4^2+1\right)\left(4^4+1\right)\left(4^8+1\right)...\left(4^{256}+1\right)\)
\(=\frac{1}{3}\left(4-1\right)\left(4+1\right)\left(4^2+1\right)\left(4^4+1\right)...\left(4^{256}+1\right)\)
\(=\frac{1}{3}\left(4^2-1\right)\left(4^2+1\right)\left(4^4+1\right)...\left(4^{256}+1\right)\)
\(=\frac{1}{3}\left(4^4-1\right)\left(4^4+1\right)...\left(4^{256}+1\right)\)
\(=\frac{1}{3}\left(4^{512}-1\right)\)
