I would like to use the options strictMath with less, when using angular-cli, but I don't know how to do this.
I'm using the current last version of angular-cli:
angular-cli: 1.0.0-beta.19-3
node: 6.9.1
os: win32 x64
So what do you want to do, specify less or more options?
:D Jokes aside, up until now almost no additional configuration can be specified.
What you can do, is access the angular-cli folder inside node_modules and modify LESS compiler configuration there.
Keep in mind, that after updating the angular-cli you will have to reapply your changes.
The angular-cli team plans to make more configuration accessible in a future version (post final version).