1) √1,8 * √7/9 *√5 3/5 = √(0,2*9) * √7/9 *√28/5 =
<u> √9 * √7*√28</u> <u>√7*√7*√4 </u>
= √0,2 * √9 * √5 = √1/5 * √5 =
<u> √1 * 7 * 2 </u> <u> 14 </u>
= √5 * √5 = 5 = 2,8
2) √1 3/8 * √5 1/2 - √ (12,5² - 3,5²)/ 2*128 =
√11/8 * √11/2 - <u>√ (12,5² - 3,5²)</u> = <u> √11 *√11</u> <u>√ (12,5 - 3,5)</u><u>(12,5+ 3,5)</u> =
√ 2*128 √8*√2 * √ 2*√2*√64
<u> 11 </u> <u>√ 9 *√ 16 </u><u /> <u> 11 * 3 *4 </u> <u> 33</u> <u> 1 </u>
= √4*√2*√2 * 2*8 = 2 * 2 * 16 = 16 = 2 16
A) 15-5x<8x+2
13x>13
x>1 (1;∞)
б) 5x^2+22x+15>0
x=1/5(-11+-√(121-75))=1/5(-11+-√46)
x<(-11-√46)/5 U x>(√46-11)/5
X^2+y^2-8x+12y+52=0
<span>x^2-2*x*4+4^2+y^2+2*y*6y+6^2=0 </span>
<span>(x-4)^2+(y+6)^2=0 </span>
<span>равенство выполняется при </span>
<span>x-4=0 </span>
<span>y+6=0 </span>
<span>и получаем </span>
<span>x=4 </span>
<span>y=-6</span>