Question

tính nhanh

a) 37²+2.37.13+13²

b) 35² +24²-48.35

c) -1²+2²+3²+4²-5²+6²+........-99²+100²

Answer 1

a) \(37^2+2\cdot37\cdot13+13^2\)

\(=1369+962+169\)

\(=2500\)

b) \(35^2+24^2-48\cdot35\)

\(=125+576-1680\)

\(=121\)

c) sai quy luật

Answer 2

\(a,37^2+2.37.13+13^2=\left(37+13\right)^2=50^2= 2500\)

\(b,35^2+24^2-2.35.24=\left(35-24\right)^2=11^2=121\)