已知tanα=3,则2sin²α+3sinαcosα+5cos²α的值,
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![已知tanα=3,则2sin²α+3sinαcosα+5cos²α的值,](/uploads/image/z/3984561-9-1.jpg?t=%E5%B7%B2%E7%9F%A5tan%CE%B1%3D3%2C%E5%88%992sin%26%23178%3B%CE%B1%2B3sin%CE%B1cos%CE%B1%2B5cos%26%23178%3B%CE%B1%E7%9A%84%E5%80%BC%2C)
已知tanα=3,则2sin²α+3sinαcosα+5cos²α的值,
已知tanα=3,则2sin²α+3sinαcosα+5cos²α的值,
已知tanα=3,则2sin²α+3sinαcosα+5cos²α的值,
tanα=sinα/cosα=3
sinα=3cosα
sin²α+cos²α=1
10cos²α=1
cos²α=1/10
2sin²α+3sinαcosα+5cos²α
=18cos²α+9cos²α+5cos²α
=32cos²α
=32/10
=3.2
3.2