a) Biểu thức có nghĩa khi $1-4x\ge 0\Rightarrow x\le \dfrac 1 4$
b) Biểu thức có nghĩa khi $-x^2\ge 0\Rightarrow x^2\le 0$
Mà $x^2\ge 0 \forall x\in \mathbb{R}$ nên biểu thức có nghĩa khi $x=0$
Ta có :
a) 2 - $\sqrt{1 - 4x }$ có nghĩa khi 1 - 4x ≥ 0
⇒ 1 ≥ 4x
⇔ x ≤ `1/4`
Vậy x ≤ `1/4` thì 2 - $\sqrt{1 - 4x }$ có nghĩa
b) 3 + $\sqrt{ - x^2 }$
Do `x^2` ≥ 0
⇒ -`x^2` ≤ 0
⇒ 3 + $\sqrt{ - x^2 }$ có nghĩa khi $\sqrt{ - x^2 }$ ≥ 0
⇒ x = 0
Vậy x = 0 thì 3 + $\sqrt{ - x^2 }$ có nghĩa
chỉ việc trả lời k phải viết đoạn
Máy nổ tưng tưng bạn nhắn , cả nhà nghi có bồ🥲 ____________________________________________ Vẽ cái điện thoại rung Full màu full line, chân thật vào
tìm giá trị lớn nhất của biểu thức A= 109 - |x - $\frac{1}{2}$ | B= 2021 - ( x + $\frac{3}{2}$ )^2
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làm hộ em ý C ạ em ko biết làm huhu
Các bạn ơi giúp mình với Ai làm được mình đánh giá 5 sao cho
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M.n giúp em vs ạ😊😊 Cho 2 đường thẳng yt và xz cắt nhau tại O.Biết góc xÔy - yÔz = 20°.Tính các góc còn lại.. lu mọi người nhiều lắm
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