Question

(2√3-√5)²+(3√2-7)(3√2+7)+√240
Calculeaza

Answer 1

(2√3-√5)²introduc sub radica (o sa vezi mai tarziu de ce)
2√3=√2²×3=√4×4=√12
deci (2√3-√5)² va deveni (√12-√5)²=(√12)²-2×√12×√5+(√5)²=12-2√12×√5+5=17-2√12×√52√12 il introduc sub radical=√2²×12=√4x12=√48
deci 17-2√12×√5=17-√48×√5=17-√240
(3√2-7)(3√2+7)3√2 introduc sub radical=√3²×2=√9×2=√18
(3√2-7)(3√2+7) va devani (√18-7)(√18+7)=(√18)²-7²=18-49=-31acum exercitiul (2√3-√5)²+(3√2-7)(3√2+7)+√240=17-√240+(-31)+√240=17-31=-14