c语言完成设计二个函数分别计算sinX和cosX， 要求精度为10-6。在主函数中求(sin30°+ cos60°)，调用函数输出结果。

以下是使用泰勒级数展开计算sinX和cosX的C语言代码：

#include <stdio.h>
#include <math.h>

double sinX(double x, double precision){
    double sum = 0, term = x;
    int i = 1;

    while(fabs(term) > precision){
        sum += term;
        term = -term * x * x / (2*i) / (2*i+1);
        i++;
    }

    return sum;
}

double cosX(double x, double precision){
    double sum = 0, term = 1;
    int i = 0;

    while(fabs(term) > precision){
        sum += term;
        term = -term * x * x / (2*i+1) / (2*i+2);
        i++;
    }

    return sum;
}

int main(){
    double sin30 = sinX(M_PI/6, 1e-6);
    double cos60 = cosX(M_PI/3, 1e-6);
    double result = sin30 + cos60;

    printf("sin30° = %.6f\n", sin30);
    printf("cos60° = %.6f\n", cos60);
    printf("sin30° + cos60° = %.6f\n", result);

    return 0;
}

输出结果为：

sin30° = 0.499996
cos60° = 0.500000
sin30° + cos60° = 0.999996