You can change viewport antialiasing in the customise menu under viewports>configure driver. but upping that will lower performance in the viewports.
When you render with scanline you shouldnt have a problem with the default settings when rendering most things unless you have anti-aliasing unchecked in the render settings. With vray you have many more options and using adaptive subdivision you can really crank up the antialiasing. thats only really usefull if you are getting buzzing on small objects like leaves or grass in your animations (Its also great to set it below one sample Ie: -2,-1 to get very fast test renders). Using two level anti aliasing with settings like min 1 max 7 should be high enough for nearly all your work.
Maybe post an image so we can see the effect.

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I'm using mental Ray render this is the render

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In mental ray you need to increase the sampling quality in the rendering menu.
Theres minimum maximum values like vray. set it to something like 1, 16.

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thanks a lot bro SOLVED

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Never give UP.

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