if I have data in cells A2 through M2 is there a formula I could use to
identify and differences in the data.

Ex.

A2 B2 C2 D2 E2 F2 G2 H2 I2 J2 K2 L2 M2
7 7 7 7 7 8 7 7 7 7 7 7 7

Is there a formula that would look at everything in this row and if it sees
the same value it would display a "yes" and if not it would display a "no".
Since the example has an "8" in F2 then it would display a no.

Thanks,