Répondre :
X = √72
= √2*36 = 6√2
y = √98 = √2*49 = 7√2
x² - y² = (√72)² - (√98)²
x² - y² = 72 -98 = -26
x + y = 6√2 + 7√2
x + y = √2( 6 + 7)
x + y = √2( 13)
x + y = 13√2
y = √98 = √2*49 = 7√2
x² - y² = (√72)² - (√98)²
x² - y² = 72 -98 = -26
x + y = 6√2 + 7√2
x + y = √2( 6 + 7)
x + y = √2( 13)
x + y = 13√2