math/big: fix minor documentation issue

Change-Id: Ib42f75c03573cec16801b79a6eb9b1b542028f4f
Reviewed-on: https://go-review.googlesource.com/7524Reviewed-by: Alan Donovan <adonovan@google.com>

src/math/big/float.go

@@ -289,7 +289,7 @@ func (z *Float) setExp(e int64) {
 // not require 0.5 <= |mant| < 1.0. Specifically:
 //
 //	mant := new(Float)
-//	new(Float).SetMantExp(mant, x.SetMantExp(mant)).Cmp(x) == 0
+//	new(Float).SetMantExp(mant, x.SetMantExp(mant)).Cmp(x).Eql() is true
 //
 // Special cases are:
 //

src/math/big/float_test.go

@@ -279,7 +279,7 @@ func TestFloatSetMantExp(t *testing.T) {
 		}
 		// test inverse property
 		mant := new(Float)
-		if z.SetMantExp(mant, want.MantExp(mant)).Cmp(want) != 0 {
+		if z.SetMantExp(mant, want.MantExp(mant)).Cmp(want).Neq() {
 			t.Errorf("Inverse property not satisfied: got %s; want %s", z.Format('g', 10), test.z)
 		}
 	}