Question

Thực hiện phép tính:

a. \(\sqrt{25}+2\sqrt{49}\)

b. \(\sqrt{16}.\sqrt{25}+\sqrt{169}:\sqrt{49}\)

c. \(\sqrt{\left(3-\sqrt{7}\right)^2}+\sqrt{7}\)

d. \(2\sqrt{3}-\sqrt{75}+2\sqrt{12}\)

Answer 1

a)\(\sqrt{25}+2\sqrt{49}=5+2\cdot7=5+14=19\)
b) \(\sqrt{16}\cdot\sqrt{25}+\sqrt{169}:\sqrt{49}=4\cdot5+13:7=20+\dfrac{13}{7}\) = \(\dfrac{153}{7}\)
c) \(\sqrt{\left(3-\sqrt{7}\right)^2}+\sqrt{7}=3-\sqrt{7}+\sqrt{7}=3\)
d) \(2\sqrt{3}-\sqrt{75}+2\sqrt{12}=2\sqrt{3}-5\sqrt{3}+4\sqrt{3}\) \(=\sqrt{3}\)