# I am confused between selection of limits for joint distribution [duplicate]

$$f(x,y)=2y \\ 0
## marked as duplicate by whuber♦ probability StackExchange.ready(function() { if (StackExchange.options.isMobile) return; $('.dupe-hammer-message-hover:not(.hover-bound)').each(function() { var$hover = $(this).addClass('hover-bound'),$msg = $hover.siblings('.dupe-hammer-message');$hover.hover( function() { $hover.showInfoMessage('', { messageElement:$msg.clone().show(), transient: false, position: { my: 'bottom left', at: 'top center', offsetTop: -7 }, dismissable: false, relativeToBody: true }); }, function() { StackExchange.helpers.removeMessages(); } ); }); }); Jan 11 at 17:23
• Hi, welcome. Please add the self-study tag and read its wiki. Here are some hints: 1) Draw $0 < y < 1$ in the $xy$-plane. 2) Draw $x = y$. 3) Where is the $x$-coordinate smaller than $y$-coordinate? – Jim Jan 11 at 16:37