Question

Giúp mik với ạk
^\(_3\)^

Answer 1

bài này tính ko dc, chỉ có rút gọn thôi :))

\(\dfrac{3sin\left(a\right)+3cos\left(a\right)}{1+2sin\left(a\right).cos\left(a\right)}=\dfrac{3\left(sin\left(a\right)+cos\left(a\right)\right)}{sin^2\left(a\right)+2sin\left(a\right).cos\left(a\right)+cos\left(a\right)}\\ =\dfrac{3\left(sin\left(a\right)+cos\left(a\right)\right)}{\left(sin\left(a\right)+cos\left(a\right)\right)^2}=\dfrac{3}{sin\left(a\right)+cos\left(a\right)}\)

p/s : \(sin^2\left(a\right)+cos^2\left(a\right)=1\) (t/c trong SGK)