1)4,8*2,8=13,44
2)4,8*7,1=34,08
3)13,44+34,08=47,52
6-в = 0 ; -в = -6; в = 6
3 - √3= √9 - √3 = √6
10 + 5√3 = 10 + √25·√3 = √100 + √75 = √175
90- 9√9 = 9( 10 - √9) = 9(√100 - √9) = 9√91
20 + 60√7= 20(1 + 3√7) = 20(√1 + √63) = 20(√64) = 20 · 8 = 160
√10 -√6 = √4 = 2
√14 + √39=√53
19 - а² = 0; -а² = -19 ; а² = 19 ; а = √19 ; а = -√19
25-р=0; р=25
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(2+√17)²= 4 + 2√17 + 2 √17 + 17 = 21 + 4√17
(√3-1)² = 3 -2√3 + 1 = 4 - 2√3 = √16 - √12 = √4 = 2
(√6+√12)²= 6 + √144 + 12 = 18 + 12 = 30
(3 - √8)² = 9 -6√8 + 8 = 17 -6√8
(√2 - √х)² = 2 -√4х +х = 2 + х - 2√х = 0 ; 4+ х² -4х =0 ; D=16 - 4·1·4= 0 ; х = 4/2 = = 2
(√14 + √22)²= 14 + 2√308 + 22 = 36 + 2√308 = 2(18 + √308) = 2√632
11 - в² = 0; в² = 11 ; в = <u />-√11 ; в = √11
21 -9х²= 0 ; х² =21 / 9; х = - √21/3 ; х =√21/3
с²-8 = 0 ; с = √8 ; с = -√8
16а²- 5 = 0 ; а² =5/16 ; а = √5/4 ; а = -√5/4
<span> (d^18+s^18)^2−(d^18−s^18)^2−d^2s^2=
d</span>³⁶+2d¹⁸s¹⁸+s³⁶-d³⁶+2d¹⁸s¹⁸-s³⁶-d²s²=4d¹⁸s¹⁸-d²s²=d²s²(4d¹⁶s¹⁶-1)=
d²s²(2d⁸s⁸-1)(2d⁸s⁸+1)
Под одной чертой дроби - 6х(5-х)(5+х)/ (х-5)18х^2=-х(5-х)(5+х)/(5-х)3=-5х+х^2/3=-15х-3х^2=15х+3х^2=3х(5+х)