Suppose corr(X,Y)=0.5 and corr(X,Z)=0.5, where X, Y, and Z are RVs. Is the correlation between Y and Z equal to 1? If not, is it possible for Y and Z to be uncorrelated?

My intuition about this is mixed, and I haven't been able to derive any conclusions using the definitions (i.e. cov(X,Y)=E(XY)-e(X).)

Thanks in advance for your help!