diff --git a/src/intro.jl b/src/intro.jl
index 2d3748d..443d0cc 100644
--- a/src/intro.jl
+++ b/src/intro.jl
@@ -138,7 +138,7 @@ function derive(ex, x)
   @capture(ex, a_ + b_) ? :($(derive(a, x)) + $(derive(b, x))) :
   @capture(ex, a_ * b_) ? :($a * $(derive(b, x)) + $b * $(derive(a, x))) :
   @capture(ex, a_^n_Number) ? :($(derive(a, x)) * ($n * $a^$(n-1))) :
-  @capture(ex, a_ / b_) ? :($b * $(derive(a, x)) - $a * $(derive(b, x)) / $b^2) :
+  @capture(ex, a_ / b_) ? :(($b * $(derive(a, x)) - $a * $(derive(b, x))) / $b^2) :
   error("$ex is not differentiable")
 end
 
@@ -170,7 +170,7 @@ function derive(ex, x)
   @capture(ex, a_ + b_) ? addm(derive(a, x), derive(b, x)) :
   @capture(ex, a_ * b_) ? addm(mulm(a, derive(b, x)), mulm(b, derive(a, x))) :
   @capture(ex, a_^n_Number) ? mulm(derive(a, x),n,:($a^$(n-1))) :
-  @capture(ex, a_ / b_) ? :($(mulm(b, derive(a, x))) - $(mulm(a, derive(b, x))) / $b^2) :
+  @capture(ex, a_ / b_) ? :(($(mulm(b, derive(a, x))) - $(mulm(a, derive(b, x)))) / $b^2) :
   error("$ex is not differentiable")
 end
 
@@ -315,7 +315,7 @@ function derive(ex, x, w)
   @capture(ex, a_ + b_) ? push!(w, addm(derive(a, x, w), derive(b, x, w))) :
   @capture(ex, a_ * b_) ? push!(w, addm(mulm(a, derive(b, x, w)), mulm(b, derive(a, x, w)))) :
   @capture(ex, a_^n_Number) ? push!(w, mulm(derive(a, x, w),n,:($a^$(n-1)))) :
-  @capture(ex, a_ / b_) ? push!(w, :($(mulm(b, derive(a, x, w))) - $(mulm(a, derive(b, x, w))) / $b^2)) :
+  @capture(ex, a_ / b_) ? push!(w, :(($(mulm(b, derive(a, x, w))) - $(mulm(a, derive(b, x, w)))) / $b^2)) :
   error("$ex is not differentiable")
 end
 
@@ -349,7 +349,7 @@ function derive(w::Wengert, x)
     Δ = @capture(ex, a_ + b_) ? addm(d(a), d(b)) :
         @capture(ex, a_ * b_) ? addm(mulm(a, d(b)), mulm(b, d(a))) :
         @capture(ex, a_^n_Number) ? mulm(d(a),n,:($a^$(n-1))) :
-        @capture(ex, a_ / b_) ? :($(mulm(b, d(a))) - $(mulm(a, d(b))) / $b^2) :
+        @capture(ex, a_ / b_) ? :(($(mulm(b, d(a))) - $(mulm(a, d(b)))) / $b^2) :
         error("$ex is not differentiable")
     ds[v] = push!(w, Δ)
   end
@@ -381,7 +381,7 @@ function derive_r(w::Wengert, x)
     elseif @capture(ex, a_^n_Number)
       d(a, mulm(Δ, n, :($a^$(n-1))))
     elseif @capture(ex, a_ / b_)
-      d(a, push!(w, mulm(Δ, b)))
+      d(a, push!(w, :($(mulm(Δ, b))/$b^2)))
       d(b, push!(w, :(-$(mulm(Δ, a))/$b^2)))
     else
       error("$ex is not differentiable")
diff --git a/src/tracing.jl b/src/tracing.jl
index e475934..c7ed824 100644
--- a/src/tracing.jl
+++ b/src/tracing.jl
@@ -225,8 +225,8 @@ function derive(w::Tape, xs...)
     elseif @capture(ex, a_^n_Number)
       d(a, Δ * n * val(a) ^ (n-1))
     elseif @capture(ex, a_ / b_)
-      d(a, Δ * val(b))
-      d(b, -Δ*val(a)/val(b)^2)
+      d(a, Δ * val(b)/val(b)^2)
+      d(b, -Δ * val(a)/val(b)^2)
     else
       error("$ex is not differentiable")
     end
diff --git a/src/utils.jl b/src/utils.jl
index d7c0aa6..9b3257a 100644
--- a/src/utils.jl
+++ b/src/utils.jl
@@ -99,7 +99,7 @@ function derive(w::Wengert, x; out = w)
     Δ = @capture(ex, a_ + b_) ? addm(d(a), d(b)) :
         @capture(ex, a_ * b_) ? addm(mulm(a, d(b)), mulm(b, d(a))) :
         @capture(ex, a_^n_Number) ? mulm(d(a),n,:($a^$(n-1))) :
-        @capture(ex, a_ / b_) ? :($(mulm(b, d(a))) - $(mulm(a, d(b))) / $b^2) :
+        @capture(ex, a_ / b_) ? :(($(mulm(b, d(a))) - $(mulm(a, d(b)))) / $b^2) :
         @capture(ex, sin(a_)) ? mulm(:(cos($a)), d(a)) :
         @capture(ex, cos(a_)) ? mulm(:(-sin($a)), d(a)) :
         @capture(ex, exp(a_)) ? mulm(v, d(a)) :
@@ -127,7 +127,7 @@ function derive_r(w::Wengert, x)
     elseif @capture(ex, a_^n_Number)
       d(a, mulm(Δ, n, :($a^$(n-1))))
     elseif @capture(ex, a_ / b_)
-      d(a, push!(w, mulm(Δ, b)))
+      d(a, push!(w, :($(mulm(Δ, b))/$b^2)))
       d(b, push!(w, :(-$(mulm(Δ, a))/$b^2)))
     else
       error("$ex is not differentiable")