Đáp án:
`a)` `=45/4`
`b)` `=-997/16`
Giải thích các bước giải:
`4/5.(7/2+1/4)^2`
`=4/5.(14/4+1/4)^2`
`=4/5.(15/4)^2`
`=4/5 . 225/16`
`=45/4`
`(1,5+5/2)^2 . 1/2-4:4/5 .(7/2+1/4)^2`
`=(3/2+5/2)^2 . 1/2-4:4/5 .(7/2+1/4)^2`
`=(8/2)^2 . 1/2-4:4/5 .(14/4+1/4)^2`
`=4^2 . 1/2-4:4/5 .(15/4)^2`
`=16 . 1/2-4:4/5 . 225/16`
`=8-5 . 225/16`
`=8-1125/16`
`=-997/16`