Erro na Instalação do EntityFrameworkCore

Eu estava tentando instalar o Entity Framework com comando "Install-Package Microsoft.EntityFrameworkCore" no Package Manager Console e deu esse erro:

Installing Microsoft.EntityFrameworkCore 2.0.0.
Install-Package : Package Microsoft.EntityFrameworkCore 2.0.0 is not compatible with netcoreapp1.1 
(.NETCoreApp,Version=v1.1). Package Microsoft.EntityFrameworkCore 2.0.0 supports: netstandard2.0 
(.NETStandard,Version=v2.0)
At line:1 char:1
+ Install-Package Microsoft.EntityFrameworkCore
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [Install-Package], Exception
    + FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PackageManagement.PowerShellCmdlets.InstallPackageCom 
   mand

Install-Package : One or more packages are incompatible with .NETCoreApp,Version=v1.1.
At line:1 char:1
+ Install-Package Microsoft.EntityFrameworkCore
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [Install-Package], Exception
    + FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PackageManagement.PowerShellCmdlets.InstallPackageCom 
   mand

Install-Package : Package restore failed. Rolling back package changes for 'CasaDoCodigo.Aula4'.
At line:1 char:1
+ Install-Package Microsoft.EntityFrameworkCore
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [Install-Package], Exception
    + FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PackageManagement.PowerShellCmdlets.InstallPackageCom 
   mand

O que eu posso fazer pra corrigir?