Tính
1) \(-0.3.\sqrt{\left(-0.3\right)^2}\)
2) \(36:\sqrt{2.3^2.18}-\sqrt{169}:13\)
Bạn nào giúp mình với nha, thanks ạ!
Tính
a) \(\sqrt{\left(2-\sqrt{3}\right)^2}+\sqrt{\left(\sqrt{3}+1\right)^2}\)
b) \(\sqrt{16}.\sqrt{25}+\sqrt{196}:\sqrt{49}\)
c) \(-0.3.\sqrt{\left(-0.3\right)^2}\)
d) \(36:\sqrt{2.3^2.18}-\sqrt{169}:13\)
Bạn nào giải từng bước giúp mình với, mình cảm ơn nhiều
tính
a) \(\sqrt{16}.\sqrt{25}+\sqrt{196}:\sqrt{49}\)
b) 36 : \(\sqrt{2.3^2.18}-\sqrt{169}\)
c) \(\sqrt{\sqrt{81}}\)
d) \(\sqrt{3^2+4^2}\)
a: \(=4\cdot5+14:7\)
=20+2
=22
\(36:\sqrt{2.3^2.18}-\sqrt{169}\)
\(36:\sqrt{2.3^2.18}-\sqrt{169}\)
<=> 36 : \(\sqrt{324}-\sqrt{169}\)
<=> 36 : 18-13
<=> 2-13
=> -11
Bạn tự kết luận nhé !
Tính:
a. \(\sqrt{16}.\sqrt{25}+\sqrt{196}:\sqrt{49};\)
b. \(36:\sqrt{2.3^2.18}-\sqrt{169};\)
c. \(\sqrt{\sqrt{81}};\)
d. \(\sqrt{3^2+4^2}.\)
a) \(\sqrt{16}\cdot\sqrt{25}+\sqrt{196}:\sqrt{49}\)
\(=\sqrt{16\cdot25}+\sqrt{196:49}\)
\(=20+2=22\)
b) \(36:\sqrt{2\cdot3^2\cdot18}-\sqrt{169}\)
\(=36:\sqrt{324}-\sqrt{169}\)
\(=36:18-13=2-13=-11\)
c) \(\sqrt{\sqrt{81}}\)
\(=\sqrt{9}=3\)
d) \(\sqrt{3^2+4^2}\)
\(=\sqrt{9+16}=\sqrt{25}=5\)
a) \(\sqrt{16}.\sqrt{25}+\sqrt{196}\div\sqrt{49}\)
\(=4.5+14:7\)
\(=20+2=22\)
b) \(36:\sqrt{2.3^2.18}-\sqrt{169}\)
\(=36:18-13=-11\)
c) \(\sqrt{\sqrt{81}}=\sqrt{9}=3\)
d) \(\sqrt{3^2+4^2}=\sqrt{25}=5\)
\(\sqrt{\left(-0.3\right)^2}\)
Giải các phương trình sau :
\(\left(\sqrt{1-\sqrt{x}}+\sqrt{1+\sqrt{x}}\right)\left(2+2\sqrt{1-x}\right)\)
\(\sqrt{x}\sqrt{3x-2}=x^2+1\)
Giúp mình với các bạn ơi ! thanks các bn nhó
\(1.\sqrt{\left(2+\sqrt{7}\right)^2-\sqrt{\left(2-\sqrt{7}\right)^2}}\)
\(2.\sqrt{\left(3\sqrt{5}-5\sqrt{2}\right)^2}-\sqrt{\left(5\sqrt{2}+3\sqrt{5}\right)^2}+10\sqrt{5}\)
\(3.\sqrt{10+2\sqrt{21}}-\sqrt{10-2\sqrt{21}}\)
\(4.\sqrt{6+2\sqrt{5-\sqrt{13+4\sqrt{3}}}}\)
Nếu được thì các bạn giải thích giúp mình với ạ :3, mình cảm ơn :3
\(1,\sqrt{\left(2+\sqrt{7}\right)^2-\sqrt{\left(2-\sqrt{7}\right)^2}}\) ( áp dụng hđt thứ 3 \(a^2-b^2=\left(a-b\right)\left(a+b\right)\))
\(=\sqrt{\left(2+\sqrt{7}+2-\sqrt{7}\right)\left(2+\sqrt{7}-2+\sqrt{7}\right)}\)
\(=\sqrt{4\cdot\sqrt{7}}\)
\(2,\sqrt{\left(3\sqrt{5}-5\sqrt{2}\right)^2}-\sqrt{\left(5\sqrt{2}+3\sqrt{5}\right)^2}\)
\(\Leftrightarrow\sqrt{\left(3\sqrt{5}-5\sqrt{2}\right)^2}=\sqrt{\left(5\sqrt{2}+3\sqrt{5}\right)^2}\)
\(\Leftrightarrow\left(3\sqrt{5}-5\sqrt{2}\right)^2=\left(5\sqrt{2}+3\sqrt{5}\right)^2\)
\(\Leftrightarrow\left(3\sqrt{5}-5\sqrt{2}\right)^2-\left(5\sqrt{2}+3\sqrt{5}\right)^2\)
\(=\left(3\sqrt{5}-5\sqrt{2}+5\sqrt{2}+3\sqrt{5}\right)\left(3\sqrt{5}-5\sqrt{2}-5\sqrt{2}-3\sqrt{5}\right)\)
\(=6\sqrt{5}\cdot\left(-10\sqrt{2}\right)\)
\(3,\sqrt{10+2\sqrt{21}}-\sqrt{10-2\sqrt{21}}\)
\(\Leftrightarrow\sqrt{10+2\sqrt{21}}=\sqrt{10-2\sqrt{21}}\)
\(\Leftrightarrow10+2\sqrt{21}=10-2\sqrt{21}\)
\(\Leftrightarrow4\sqrt{21}\)
cuối lười tính nên thôi nhá :>
1)\(\sqrt{x+3}\) > 2
2) \(\dfrac{1+\sqrt{x}}{\sqrt{x}-2}\)<1
3) \(\left(\sqrt{x}-1\right)\).\(\left(\sqrt{x}-3\right)\)-5=\(\sqrt{x}\) \(\left(\sqrt{x}+2\right)-5\)
tìm x mn giúp mình nha plsss
1: ĐKXĐ: x+3>=0
=>x>=-3
\(\sqrt{x+3}>2\)
=>x+3>4
=>x>4-3=1
2: ĐKXĐ: \(\left\{{}\begin{matrix}x>=0\\x< >4\end{matrix}\right.\)
\(\dfrac{\sqrt{x}+1}{\sqrt{x}-2}< 1\)
=>\(\dfrac{\sqrt{x}+1}{\sqrt{x}-2}-1< 0\)
=>\(\dfrac{\sqrt{x}+1-\sqrt{x}+2}{\sqrt{x}-2}< 0\)
=>\(\dfrac{3}{\sqrt{x}-2}< 0\)
=>\(\sqrt{x}-2< 0\)
=>\(\sqrt{x}< 2\)
=>0<=x<4
3: ĐKXĐ: x>=0
\(\left(\sqrt{x}-1\right)\left(\sqrt{x}-3\right)-5=\sqrt{x}\left(\sqrt{x}+2\right)-5\)
=>\(x-4\sqrt{x}+3-5=x+2\sqrt{x}-5\)
=>\(x-4\sqrt{x}-2-x-2\sqrt{x}+5=0\)
=>\(-6\sqrt{x}+3=0\)
=>\(-6\sqrt{x}=-3\)
=>\(\sqrt{x}=\dfrac{1}{2}\)
=>x=1/4(nhận)