来自任风采的问题
【⑴1+sin2θ-cos2θ/1+sin2θ+cos2θ⑵已知13sinα+5cosβ=9,13cosα+5sinβ=15,求cos(α+⑴1+sin2θ-cos2θ/1+sin2θ+cos2θ⑵已知13sinα+5cosβ=9,13cosα+5sinβ=15,求cos(α+β)的值】
⑴1+sin2θ-cos2θ/1+sin2θ+cos2θ⑵已知13sinα+5cosβ=9,13cosα+5sinβ=15,求cos(α+
⑴1+sin2θ-cos2θ/1+sin2θ+cos2θ
⑵已知13sinα+5cosβ=9,13cosα+5sinβ=15,求cos(α+β)的值
1回答
2020-06-2407:57