Question

Cho a + b + c=0, a² + b² + c² = 14

Tính a⁴ + b⁴ + c⁴

Answer 1

(ab+ac+bc)2=49" role="presentation" style="border:0px; direction:ltr; display:inline-block; float:none; font-size:18.06px; line-height:0; margin:0px; max-height:none; max-width:none; min-height:0px; min-width:0px; padding:1px 0px; position:relative; white-space:nowrap; word-spacing:normal; word-wrap:normal" class="MathJax_CHTML mjx-chtml">(ab+ac+bc)2=49

(ab)2+(bc)2+(ac)2=49" role="presentation" style="border:0px; direction:ltr; display:inline-block; float:none; font-size:18.06px; line-height:0; margin:0px; max-height:none; max-width:none; min-height:0px; min-width:0px; padding:1px 0px; position:relative; white-space:nowrap; word-spacing:normal; word-wrap:normal" class="MathJax_CHTML mjx-chtml">(ab)2+(bc)2+(ac)2=49

a4+b4+c4=(a2+b2+c2)2−2(ab)2−2(ac)2−2(bc)2=" role="presentation" style="border:0px; direction:ltr; display:inline-block; float:none; font-size:18.06px; line-height:0; margin:0px; max-height:none; max-width:none; min-height:0px; min-width:0px; padding:1px 0px; position:relative; white-space:nowrap; word-spacing:normal; word-wrap:normal" class="MathJax_CHTML mjx-chtml">a4+b4+c4=(a2+b2+c2)2−2(ab)2−2(ac)2−2(bc)2= 98

t i c k nhé 5747457567568768769987907807956845784676