b)[(-3/4)⁶ :(-3/4)⁴ +(1/2)⁷ :(1/2)⁵]³ :(39/16)²=
=[(3/4)² +(1/2)² ]³ :(39/16)²=
=(9/16 +1/4)³ :(39/16)²=
=[(9+4)/16]³ :(39/16)²=
=(13/16)³ :(3×13/16)²=
=13³/16³ ×16²/3²×13²=
=13/16 ×1/3²=
=13/144
c)(4/5)¹⁰ :(4/5)⁸ -(1+1/5)² :(1-1/5) +1/5=
=(4/5)² -(6/5)² :(4/5) +1/5=
=(4/5)² -(6/5)² ×(5/4) +1/5=
=(4/5)² -(2²×3²/5² ×5/2² +1/5=
=16/25 -9/5 +1/5=
=16/25 -8/5 =
=(16-40)/25=
=-24/25
