\(2020-\left[45-\left(6-1\right)^2\right]+1990^0\\ =2020-\left[45-5^2\right]+1\\ =2020-\left[45-25\right]+1\\ =2020-20+1\\ =2000+1\\ =2001\)
`@Muopngot k h a t`
`2020-[45-(6-1)^2]+1992^0`
`=2020-[45-5^2]+1`
`=2020-[45-25]+1`
`=2020-20+1`
`=2000+1`
`=2001`
2020−[45−(6−1)2]+19900=2020−[45−52]+1=2020−[45−25]+1=2020−20+1=2000+1=2001