X²=a a²-13a+36≤0 a1+a2=13 U a1*a2=36 a1=4 U a2=9 + _ + ----------------[4]--------------[9]--------------- 4≤a≤9 {x²≥4⇒(x-2)(x+2)≥0⇒x≤-2 U x≥2 {x²≤9⇒(x-3)(x+3)≤0⇒-3≤x≤3 \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ ///////////////////////////////// ----------[-3]------------[-2]----------[2]-----------[3]--------------- ///////////////////////////////////////////////////////// x↑[-3;-2] U [2;3]
А можна пояснити це - \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ ///////////////////////////////// ----------[-3]------------[-2]----------[2]-----------[3]--------------- /////////////////////////////////////////////////////////?
tanyalyashchuk
А можна пояснити це - \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ ///////////////////////////////// ----------[-3]------------[-2]----------[2]-----------[3]--------------- /////////////////////////////////////////////////////////?
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Verified answer
X²=aa²-13a+36≤0
a1+a2=13 U a1*a2=36
a1=4 U a2=9
+ _ +
----------------[4]--------------[9]---------------
4≤a≤9
{x²≥4⇒(x-2)(x+2)≥0⇒x≤-2 U x≥2
{x²≤9⇒(x-3)(x+3)≤0⇒-3≤x≤3
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ /////////////////////////////////
----------[-3]------------[-2]----------[2]-----------[3]---------------
/////////////////////////////////////////////////////////
x↑[-3;-2] U [2;3]