FactorInteger[661775625]

3^2 5^4 7^6

GCD[2^15 - 1, 2^20 - 1]

FactorInteger[2^15 - 1]

FactorInteger[2^20 - 1]

Expand[(a + b)^5]

Solve[x^2 + a x + b == 0, x]

Solve[x^3 + a x^2 + b x + c == 0, x]

Simplify[%]

D[x^2 Sqrt[x] + (x^3 - x) Sqrt[x^2 + x + 1], x]

Simplify[%]

Integrate[%, x]

D[Sqrt[(1 + x^2)/(1 - x^2)],  x]

Simplify[%]

Integrate[%, x]

Integrate[1/(x - 2)^5, {x, 0, 1}]

f[x_] := Evaluate[Integrate[1/(x - 2)^5, x]]

f[x]

f[1] - f[0]

Integrate[1/(2 + Cos[x]), {x, 0, Pi}]

f[x_] := Evaluate[Integrate[1/(2 + Cos[x]), x]]

f[x]

D[f[x], x]

Simplify[%]

f[Pi] - f[0]