Question

Folositi formulele: 1).(radical din 3+b)(radical din 3+b) 2).(7+radical din 2) 3).(a+b) totul la 2.???

Answer 1

$a).( \sqrt{3} +b)( \sqrt{3} +b)=3+ \sqrt{3} b+ \sqrt{3} b+b^2=b^2+2 \sqrt{3} b+3 \\ b).(7+ \sqrt{2} )^2=7^2 +2 \cdot 7 \cdot \sqrt{2} + \sqrt{2} ^2=49+14 \sqrt{2} +2=51+14 \sqrt{2} \\ c).(a+b)^2=a^2+2 \cdot a \cdot b+b^2=a^2+2ab+b^2$