Объяснение:
5b*(b⁻¹-5⁻²)*(b¹/²-5)⁻¹.
1. 5b*(b⁻¹-5⁻²)=5b*((1/b)-(1/5)²)=5b*((1/b)-(1/25))=5b*(25-b)/(25*b)=
=(25-b)/5=(5-√b)*(5+√b)/5=-(√b-5)*(√b+5)/5.
2. (b¹/²-5)⁻¹=(√b-5)⁻¹=1/(√b-5).
3. (-(√b-5)*(√b+5)/5)*(1/(√b-5))=-(√b+5)/5.
Объяснение:
5b*(b⁻¹-5⁻²)*(b¹/²-5)⁻¹.
1. 5b*(b⁻¹-5⁻²)=5b*((1/b)-(1/5)²)=5b*((1/b)-(1/25))=5b*(25-b)/(25*b)=
=(25-b)/5=(5-√b)*(5+√b)/5=-(√b-5)*(√b+5)/5.
2. (b¹/²-5)⁻¹=(√b-5)⁻¹=1/(√b-5).
3. (-(√b-5)*(√b+5)/5)*(1/(√b-5))=-(√b+5)/5.